Tuesday, June 30, 2009

FERTILITY

Fertility is the natural capability of giving life. As a measure, "fertility rate" is the number of children born per couple, person or population. This is different from fecundity, which is defined as the potential for reproduction (influenced by gamete production, fertilisation and carrying a pregnancy to term). Infertility is a deficient fertility.

Human fertility depends on factors of:

Human fertility

Both women and men have hormonal cycles which determine both when a woman can achieve pregnancy and when a man is most virile. The female cycle is approximately twenty-eight days long, but the male cycle is variable. Men can ejaculate and produce sperm at any time of the month, but their sperm quality dips occasionally, which scientists guess is in relation to their internal cycle.

Furthermore, age also plays a role, especially for women.

Menstrual cycle

Although women can become pregnant at any time during their menstrual cycle, peak fertility occurs during just a few days of the cycle: usually two days before and two days after the ovulation date[3]. This fertile window, varies from woman to woman, just as the ovulation date often varies from cycle to cycle for the same woman[4]. The ovule is usually capable of being fertilized for up to 48 hours after it is released from the ovary. Sperm survive inside the uterus between 48 to 72 hours on average, with the maximum being 120 hours (5 days).

These periods and intervals are important factors for couples using the rhythm method of contraception.

Female fertility

The average age of menarche in the United States is about 12.5 years.[5] In postmenarchal girls, about 80% of the cycles were anovulatory in the first year after menarche, 50% in the third and 10% in the sixth year.[6][7] Women's fertility peaks around the age of 19-24, and often declines after 30.[citation needed] With a rise in women postponing pregnancy,[8] this can create an infertility problem. Of women trying to get pregnant, without using fertility drugs or in vitro fertilization:

  • At age 30, 75% will get pregnant within one year, and 91% within four years.
  • At age 35, 66% will get pregnant within one year, and 84% within four years.
  • At age 40, 44% will get pregnant within one year, and 64% within four years.[9]

The above figures are for pregnancies ending in a live birth and take into account the increasing rates of miscarriage in the aging population. According to the March of Dimes, "about 9 percent of recognised pregnancies for women aged 20 to 24 ended in miscarriage. The risk rose to about 20 percent at age 35 to 39, and more than 50 percent by age 42".[10]

Birth defects, especially those involving chromosome number and arrangement, also increase with the age of the mother. According to the March of Dimes, "At age 25, a woman has about a 1-in-1,250 chance of having a baby with Down syndrome; at age 30, a 1-in-1,000 chance; at age 35, a 1-in-400 chance; at age 40, a 1-in-100 chance; and at 45, a 1-in-30 chance."[11]

The use of fertility drugs and/or invitro fertilization can increase the chances of becoming pregnant at a later age. Successful pregnancies facilitated by fertility treatment have been documented in women as old as 67.[12]

Doctors recommend that women over 30 who have been unsuccessful in trying to conceive for more than 6 months undergo some kind of fertility testing.[13]

Male fertility and age

Erectile dysfunction increases with age,[14] but fertility does not decline in men as sharply as it does in women. There have been examples of males being fertile at 94 years old.[14] However, evidence suggests that increased male age is associated with a decline in semen volume, sperm motility, and sperm morphology.[15] In studies that controlled for female age, comparisons between men under 30 and men over 50 found relative decreases in pregnancy rates between 23% and 38%.[15]

Cause of decline

Sperm count declines with age, with men aged 50-80 years producing sperm at an average rate of 75% compared with men aged 20-50 years. However, an even larger difference is seen in how many of the seminiferous tubules in the testes contain mature sperm;

  • In males 20-39 years old, 90% of the seminiferous tubules contain mature sperm.
  • In males 40-69 years old, 50% of the seminiferous tubules contain mature sperm.
  • In males 80 years old and older, 10% of the seminiferous tubules contain mature sperm.[14]

Recent research has suggested increased risks for health problems for children of older fathers. A large scale Israeli study found that the children of men 40 or older were 5.75 times more likely than children of men under 30 to have an autism spectrum disorder, controlling for year of birth, socioeconomic status, and maternal age.[16] Increased paternal age has also been correlated to schizophrenia in numerous studies.[17][18][19]

The American Fertility Society recommends an age limit for sperm donors of 50 years or less,[20] and many fertility clinics in the United Kingdom will not accept donations from men over 40 or 45 years of age. [21] In part because of this fact, more women are now using a take-home baby rate calculator to estimate their chances of success following invitro fertilization. [22]

References

  1. http://www.gfmer.ch/Books/Reproductive_health/The_demography_of_fertility_and_infertility.html
  2. http://www.enotes.com/public-health-encyclopedia/fecundity-fertility
  3. http://www.duofertility.com/en/my-body/my-cycle/my-fertile-period.html
  4. Creinin MD, Keverline S, Meyn LA (October 2004). "How regular is regular? An analysis of menstrual cycle regularity". Contraception 70 (4): 289–92. doi:10.1016/j.contraception.2004.04.012. PMID 15451332.
  5. Anderson SE, Dallal GE, Must A (April 2003). "Relative weight and race influence average age at menarche: results from two nationally representative surveys of US girls studied 25 years apart". Pediatrics 111 (4 Pt 1): 844–50. doi:10.1542/peds.111.4.844. PMID 12671122. http://pediatrics.aappublications.org/cgi/content/full/111/4/844?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&searchid=1&FIRSTINDEX=0&minscore=5000&resourcetype=HWCIT.
  6. Apter D (February 1980). "Serum steroids and pituitary hormones in female puberty: a partly longitudinal study". Clin. Endocrinol. (Oxf) 12 (2): 107–20. doi:10.1111/j.1365-2265.1980.tb02125.x. PMID 6249519.
  7. Apter D (February 1980). "Serum steroids and pituitary hormones in female puberty: a partly longitudinal study". Clin. Endocrinol. (Oxf) 12 (2): 107–20. doi:10.1111/j.1365-2265.1980.tb02125.x. PMID 6249519. http://www3.interscience.wiley.com/journal/119590594/abstract.
  8. http://findarticles.com/p/articles/mi_m1077/is_1_62/ai_n16807720 "Late-in-life Pregnancy"
  9. "Fertility Treatment Less Successful After 35". WebMD. http://www.webmd.com/content/article/89/100183.htm. Retrieved on July 4 2006.
  10. "Pregnancy After 35". March of Dimes. http://www.marchofdimes.com/professionals/14332_1155.asp. Retrieved on May 21 2008.
  11. "The sterility tax can be reestablished in Russia". http://russia-ic.com/business_law/in_depth/253/. Retrieved on September 22 2006.
  12. "Spanish woman ' is oldest mother'". BBC News. http://news.bbc.co.uk/2/hi/health/6220523.stm. Retrieved on 2006-12-30.
  13. Female Fertility Testing
  14. a b c Effect of Age on Male Fertility Seminars in Reproductive Endocrinology. Volume, Number 3, August 1991. Sherman J. Silber, M.D.
  15. a b Kidd SA, Eskenazi B, Wyrobek AJ (February 2001). "Effects of male age on semen quality and fertility: a review of the literature". Fertil. Steril. 75 (2): 237–48. doi:10.1016/S0015-0282(00)01679-4. PMID 11172821. http://linkinghub.elsevier.com/retrieve/pii/S0015-0282(00)01679-4.
  16. Reichenberg A, Gross R, Weiser M, et al. (September 2006). "Advancing paternal age and autism". Arch. Gen. Psychiatry 63 (9): 1026–32. doi:10.1001/archpsyc.63.9.1026. PMID 16953005. http://archpsyc.ama-assn.org/cgi/content/abstract/63/9/1026.
  17. Malaspina D, Harlap S, Fennig S, et al. (April 2001). "Advancing paternal age and the risk of schizophrenia". Arch. Gen. Psychiatry 58 (4): 361–7. doi:10.1001/archpsyc.58.4.361. PMID 11296097. http://archpsyc.ama-assn.org/cgi/pmidlookup?view=long&pmid=11296097.
  18. Sipos A, Rasmussen F, Harrison G, et al. (November 2004). "Paternal age and schizophrenia: a population based cohort study". BMJ 329 (7474): 1070. doi:10.1136/bmj.38243.672396.55. PMID 15501901.
  19. Malaspina D, Corcoran C, Fahim C, et al. (April 2002). "Paternal age and sporadic schizophrenia: evidence for de novo mutations". Am. J. Med. Genet. 114 (3): 299–303. doi:10.1002/ajmg.1701. PMID 11920852.
  20. Plas E, Berger P, Hermann M, Pflüger H (August 2000). "Effects of aging on male fertility?". Exp. Gerontol. 35 (5): 543–51. doi:10.1016/S0531-5565(00)00120-0. PMID 10978677. http://linkinghub.elsevier.com/retrieve/pii/S0531-5565(00)00120-0.
  21. Age Limit of Sperm Donors in the United Kingdom Pdf file
  22. http://www.formyodds.com

Reviewed by Bambang Widjanarko Obstetrician & Gynecologist

Can You Determine the Sex of Your Baby?

You’re trying to get pregnant and you’re wondering if there’s any way you can get that little girl or boy that you so desire. Admit it, someone told you if you eat a certain food or have sex in a certain position, you can control the sex of your baby and part of you thought, "why not?" In the case of most of these old wives tales, it can’t hurt to try, but are some of them dangerous? And remember, for all of the women who claim that one or more of these tricks worked for them, there are just as many who will tell you that they didn’t work at all!

Cultural Beliefs
The ancient Mayans believed that you could determine the sex of a baby by looking at the mother’s age at conception and the year of conception. If both numbers are even or both are odd, then the baby will be a girl. If one number is even and the other is odd, the baby is a boy. Some people will tell you that this absolutely works, but we figure the odds are about 50/50.

The Chinese also have a method for predicting the sex of a baby. The belief is that if you compare the mother’s age at conception and the month of conception you can accuratly predict the sex of the baby using a chart. A quick office poll reveals that the Chinese method has about the same rate of success as the Mayans – 50%.

Don’t feel like putting all of your faith in the Chinese or Mayan methods? Here are a few other methods that some people claim will work:

If You Want a Girl:

  • Eat lots of chocolate and other sweets If you’re not diabetic or pre-diabetic, go for it – but in moderation! We all know that too many sweets are bad for blood sugar, waist-lines and teeth.
  • Both of you should eat lots of fish and veggies It may not get you a girl, but eating healthy is never a bad idea.
  • If the woman orgasms first, you’ll have a girl/
  • The missionary position will produce girls
  • If the woman is on top you’ll have a girl

If you Want a Boy:

  • Eat lots of salty foods We’re not so sure that this is a good idea. Too much salt can cause hypertension and in some cases, stomach cancer. If you already have high-blood pressure, definitely don’t try this.
  • Eat lots of red meat
    There are a lot of vegetarians who will tell you that you can have a boy without eating any meat. While moderate intake of red meat is fine, too much does carry some health risks; consumption of too much red meat has been linked to colon cancer and heart disease. If you want to try this, consider choosing organic meat. Meat from cattle that have been fed grass contains more omega three and six fatty acids (the good fats), and less saturated fat.
  • Let the man initiate love making
  • Make love standing up
  • Lie down for a while after sex
  • Have sex while on all-fours

Other Pearls of Wisdom A common claim is that more boys are conceived on odd numbered days and more girls on even numbered days. If you want a girl, try to conceive when the moon is a quarter full and for a boy try when the moon is full. Some people claim that the time of day can affect the baby’s gender too – girls are conceived in the afternoon and boys at night.

What Doctors Say Sorry to say, the scientific community doesn’t put any stock in any pregnancy folklore. Probably because all of these methods produce no more than a 50/50 chance of conceiving a child of the sex you prefer. Of course, there are some scientific theories about how to choose the sex of your baby. The most popular one involves keeping track of your ovulation cycles and mucous production.

Another scientific method of gender selection is called Percoll density gradient centrifugation procedure, also known as "sperm spinning". The sperm is placed in a centrifuge and spun. The Y (male-producing) sperm rises to the top of the centrifuge and the X (girl-producing) sperm goes to the bottom. This method has about a 77% success rate, however it is expensive and time consuming and requires undergoing in-vitro fertilization. In other words – it’s not a try at home method.

Sexual Positon and Baby Making

Best Sexual Positions for Baby Making

Obviously, if the time is right a woman may conceive regardless of sexual position. All of us likely could cite a case where actual intercourse did not take place but pregnancy occurred! Still, if you want to optimize your odds consider these suggestions. All are speculative by scientific standards, but considered successful by parents worldwide.

Upping the Odds with Effective Positions

Missionary Position (a.k.a. Man on top): Overwhelmingly, experts and parents alike agree that having the man positioned on top offers the greatest possibility of conception. The degree of penetration combined with the prone position of the woman allows the sperm to be deposited near the cervical opening. Additional "pluses" for this position allow both partners to communicate through sensual looks, intimate kisses, touch and oral stimulation of breasts and nipples (for both partners!), and movement.

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From Behind (a.k.a. "doggy style"): The woman kneels before the man, facing away. Penetration is then from behind, enabling the man to enter with deeper thrusts and deposit the sperm close to the cervix. Due to the control this offers the man, his orgasms may be more intense as well.

Want to have even more fun with this position? The man can reach around and fondle his partner's breast or clitoris during intercourse and perhaps even following his own orgasm for additional stimulation. The woman may find she can pleasure her partner by reaching between, "tickling" his testicles gently as he moves and/or stroking the base of his penis. The resulting orgasms may surprise you both!

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Spooning: The woman lays with her back to her partner and he cuddles her from behind. Penetration will not be as deep, but both partners are often quite relaxed which can also lead to achieving conception. The woman is able to move against her partner, inviting stimulation and allowing him to enter her from behind. The man is able to manually stimulate the woman's breasts and clitoris. Gentle kisses and communication between the two of you may ignite more pleasure. Something to try? The woman may want to help guide her partner's touch. She may also be able to reach and stroke him as he enters.

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"Living on the Edge": Take this one literally! The woman lays on the edge of the bed or couch. The man can then enter from the front from either a standing or kneeling position. Like the missionary position, this allows the man to enjoy a good penetration. The unusual position may excite you both. Again, manual stimulation of both partners can add even more pleasure and intensity. Gravity, ladies, remains on your side helping the sperm meet their goal!

"Scissors": No, this is not your average "rock, paper, scissors" game! This position is one of the more unique used -- but may be just outside of the ordinary enough for you both to increase your enjoyment and result in achieving pregnancy. There are a few variations of this but the basics involve the woman lying on her side; bottom leg is between your partner's legs; top leg may be lifted up or straddled over his side. Men, lay perpendicular to your partner; bottom leg under hers; top leg between hers so the two of you are like "scissors" with the your view being your partner's back. Be certain to adjust either the angle or proximity if needed for comfort. Penetration from this position can and should be sensual for both partners.

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Trying for a Certain Gender?

Whether you want a precious baby girl or a bouncing baby boy, positioning actually may play a role (along with timing and other factors.) Male sperm (Y-chromosome) are known for being faster swimmers than their female (X-chromosome) counterparts. They also tend to die off quicker while the female sperm live longer.

Those wishing for a boy may find it best to settle on "doggy style" position. This allows the penetration to be deeper, shortening the distance the sperm carrying the Y-chromosome must travel. According to what is known as the Shettles™ method, the optimal time to conceive a male child is close to ovulation -- generally by having sexual intercourse within the window 24 hours prior to ovulation to 12 hours after. Male sperm also supposedly prefer a more alkaline environment for swimming so ladies, avoid dairy and up the sodium intake. Men, drinking caffeine before sex (NOT alcohol!) can boost the speed of your Y’s!

Dreaming of a girl? Opt for a position with shallow penetration, such as spooning. A greater window of opportunity allows the slower, but much more resilient "female sperm" to take their time in reaching their destination. These sperm typically survive three to five days, and in some (rare) cases up to seven! Female (X-chromosome) sperm tend to prefer a more acidic environment. Increasing dairy products and sweets (don't forget those more natural, healthy sources such as fruits) may provide an additional aid.

How Important is Orgasm?

What about the O-factor? Obviously, for the male's role, achieving orgasm certainly aids in distributing sperm to its intended destination. Don't forget though that female orgasm can be as equally important, particularly after the man has climaxed! The reasoning? Achieving female orgasm can improve the environment for the sperm to swim and survive. The resulting contractions help draw the sperm up and into the cervix -- ready to meet that egg and "make" a baby!

The most important dynamic is to relax and enjoy being intimate with your partner. While certainly increasing your personal knowledge and understanding of your fertility is important, you will likely find that leaving that outside the bedroom will allow you both to focus on your love and desire to pleasure one another versus feeling as if being intimate is now yet another chore on your to-do list.

For those that have been trying for a year or more may wish to seek out medical advice regarding their and/or their partner's fertility.

SEXUAL INTERCOURSE, OVULATION AND CONCEPTION

Many women who are trying to conceive want to learn when ovulation and implantation occur and what are usual miscarriage or pregnancy loss rates. Quite often the numbers women are given are based on averages, theoretical numbers and sometimes just plain guesses because it is such a difficult topic to scientifically investigate. New data comes available periodically but it is not always promptly and widely disseminated even on the Net.

When does implantation take place?

One such relatively recent study tells us that implantation does not always take place on day 7 after ovulation. In fact it very rarely does. This study by AJ Wilcox accurately determined the day of implantation by very sensitive pregnancy test (HCG) measurement compared to ovulation.

HCG hormone starts being produced when the pregnancy implants into the uterine lining. The findings in normal women trying to conceive included:

  • first appearance of HCG (implantation) occurred 6-12 days after ovulation
  • 84% of the pregnancies implanted on days 8-10 after ovulation
  • early pregnancy loss increased with later implantation -
    implantation early pregnancy loss rate
    • 13% by day 9
    • 26% on day 10
    • 52% on day 11
    • 86% on day 12 or more

Overall the total pregnancy loss up to 6 weeks was 25%. Now that seems very high to most people but keep in mind many of these pregnancy losses occurred so early that women often were not aware they were even pregnant. The normal early pregnancy loss rate that most women know about is 15-18% of clinically recognized pregnancies so almost 40% of all pregnancy loss is unrecognized.

When is the best time to have intercourse in order to get pregnant?

Wilcox had also performed previous work in 1995 (2) which demonstrated that pregnancy only occurs if intercourse occurs within the 6 days prior to and including ovulation. Intercourse after the day of ovulation does not result in pregnancy. The probability of conception ranged from 10% when intercourse occurred five days before ovulation to 33% when it occurred on the day of ovulation itself.

This is the data that suggests the best timing of intercourse in order to conceive is day 10, 12, 14 and 16 (in case of late ovulation) of a 28 day cycle or days -4, -2, 0, +2 in relation to expected ovulation in the case of cycles different than 28 days.

When should I begin testing with home urine tests?

Most home pregnancy tests that check urine beta-HCG are sensitive to 20-25 mIU/ml of HCG. The general rule-of thumb is to test at the time when you are a day late for your menses or about 15 days after ovulation. The test can be positive anywhere from about 2-3 days prior to a missed menses to 4-5 days after.

Testing really does depend upon how regular your menses are or in other words how regular ovulation occurs. If you tend to be late (longer than 28 days) with your periods or the timing of menses varies by several days each cycle, then it is better not to waste pregnancy tests by testing at day 28-29 after the last period starts.

Are ovulation prediction tests worth doing?

Pelvic ultrasound looking at the ovaries is considered the gold standard in ovulation prediction in a research setting but obviously in a practical application of a woman trying to conceive, ultrasound is not used. Urinary LH testing has been shown to have a 100% correlation with ultrasound as far as predicting the timing of ovulation. In that same study, they looked at cervical mucous changes, basal body temperatur (BBT) charts and salivary ferning. Cervical mucous changes only had a correlation of 48%, salivary ferning correlated 37% and BBT has a 30% correlation.

For the home tests that measure LH surge that immediately precedes ovulation, detection of LH occurs at above 30 mIU/ml. This means that women with polycyctic ovarian syndrome who have slightly higher resting LH values are still not falsely detected as ovulating. The urinary LH spike occurs about 24-36 hours prior to ovulation so it is very useful for women trying to conceive because it gives them a window of warning. The test will show positive for one or two days and rarely 3 days if you catch a spike right at the beginning and it is a large release of LH.

What Should You Do After Intercourse To Increase Your Chances Of Getting Pregnant?

What should you do after intercourse to increase your chances of getting pregnant? Well, ask your grandma! There are a lot of tips and tricks that suggest that you can increase your odds of getting pregnant, even after intercourse, by following certain routines. These may work with some women and might not work with the rest. Though not completely scientific, they have shown marked results in some women who swear by them. Douching for example was once a popular method to increase your chances of getting pregnant, but today it has been shrugged off as a myth.

Will having intercourse in the morning help?

Some studies claim that a man’s sperm count may be higher in the morning as compared to other times of the day. But other studies also show that the differences in sperm count are so minimal that it does not matter much in terms of getting pregnant. For example, assume that your sperm count goes from 87 million in the evening to 88 million in the morning. This may sound significant in numbers. But understand that it doesn’t change much if you are talking about a tough conception history. That’s so because, after all, it only takes one sperm to do the job.

One of the surest ways is to have intercourse as often as you can! So stop worrying about the clock and have sex whenever the mood strikes you — day or night.

Will timing intercourse during the monthly cycles help?

Yes, definitely. If you really want to swing the odds of getting pregnant in your favor, you should try and start timing sex sessions as close to ovulation as you can. For most women that’s about halfway between periods and the most fertile period in the month. Our article on ovulation will help you better understand the process and give you an idea of when you’ll ovulate.

It also helps to keep in mind that while it’s important to understand your cycle and the changing patterns of cervical mucus and basal temperature, it’s equally important to try to relax, enjoy sex and the warm feeling of being parents soon. Believe it or not, the more relaxed you are, the better your chances of conceiving.

What can we do after intercourse to increase our odds?

For most healthy couples, getting pregnant isn’t difficult, and no special arrangements need to be made beyond depositing the man’s semen into the woman’s vagina. Generally, the sperm reach the cervix within seconds of ejaculation. But if you have been trying hard and long enough, here’s a secret. Lie flat after intercourse and raise your legs to 30 degrees. This helps the cervical and vaginal muscles to relax and facilitates the movement of cervical mucus. If your man has enough sperm count and you have the right consistency of cervical mucus, this method will greatly help to increase your chances of getting pregnant.

Even doctors recommend that a woman should lie down with her legs slightly raised after intercourse to increase her chances of conception. This greatly helps in women who are trying to get pregnant because the sperm doesn’t have to fight gravity as they make their way to the egg. There is no scientific evidence of this improving the chances of getting pregnant, but many people have tried it to aid conception. It is a harmless technique and worth a shot.

Even after trying various techniques and therapies, if you still encounter trouble in conceiving, you must consult a doctor for advice on how to proceed.

NUTRITION and PREGNANCY

clip_image002A balanced diet is a basic part of good health at all times in your life. During pregnancy, your diet is even more important. The foods you eat are the main source of nutrients for your baby. As your baby grows, you will need more of most nutrients. This pamphlet will help you learn more about:

  • Good food choices for you and your baby
  • Nutrients you will need
  • Healthy weight gain

Eating right during your pregnancy is one of the best things you can do for yourself and your baby.

Before You Become Pregnant

The best time to begin eating a healthy diet is before you become pregnant. This will help you and your baby start out with the nutrients you both need.

If you are planning to become pregnant, visit your doctor. Getting good health care before you are pregnant will help you throughout your pregnancy. As part of your visit, you will be asked about your family life, work, and lifestyle, including your diet. You and your doctor will discuss how to eat right before and during your pregnancy and which nutrients are especially important, such as folic acid.

A Healthy Diet

The first step toward healthy eating is to look at the foods in your daily diet. Early in pregnancy, morning sickness can affect your eating habits. You may crave certain foods or not feel like eating. If this happens, you still should try to eat a variety of foods each day to help ensure you are getting the right amount of nutrients.

Having healthy snacks that you can eat during the day is a good way to get the nutrients and extra calories you need. You may find it easier to eat snacks and small meals throughout the day rather than three big meals a day. This also may help you avoid nausea and heartburn.

Healthy eating also means avoiding things that may be harmful. This includes alcohol (beer, wine, or mixed drinks) and illegal drugs, which may cause birth defects and other problems for the baby. Smoking cigarettes is especially harmful to a pregnant woman and her baby.

You also may want to avoid or limit your caffeine intake during pregnancy. Although some studies suggest drinking three or more cups of coffee per day may increase the risk of miscarriage, there is no proof that caffeine causes miscarriage.

Meal Planning

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Planning meals in advance can help ensure you and your family eat a balanced diet. The food pyramid developed by the U.S. Department of Agriculture can help you choose what to eat (www.mypyramid.gov) (see Table 1). It takes into account your age, sex, and your amount of daily physical activity and shows the number of servings you should have each day from each of the six food groups:

  1. Grains
  2. Vegetables
  3. Fruit
  4. Oils
  5. Milk
  6. Meat and beans

Basic Nutrients

Every diet should include proteins, carbohydrates, fats, vitamins, and minerals. To be sure your diet provides you with the right amount of nutrients, you should know which foods are good sources of each.

The RDA—recommended daily allowance—on food labels shows the levels of nutrients you need every day. During pregnancy, the RDAs are higher for most nutrients. Table 2 shows the key nutrients you and your baby will need during your pregnancy.

Extra Nutrients

Pregnant women need extra iron and folic acid, and these are usually prescribed in pill form as supplements. Sometimes a prenatal supplement that contains these two nutrients plus vitamins and minerals is recommended. Ask your doctor or nurse how your needs can be best met.

Women should take 400 micrograms of folic acid daily, in addition to a well balanced diet, for at least 1 month before pregnancy and during the first 3 months of pregnancy. This can help prevent neural tube defects, which affect the spine and skull of the fetus.

Women who have had a child with a neural tube defect are more likely to have another child with this problem. These women need much higher doses of folic acid—4 milligrams daily. It should be taken for at least 1 month before pregnancy and during the first 3 months of pregnancy. Women who need 4 milligrams should take folic acid as a separate supplement, not as part of a multivitamin.

Check with your doctor before taking any vitamins, herbs, or other supplements that are not prescribed for you. They might be harmful during pregnancy. Just because a product is natural does not mean it is safe to use during pregnancy.

Weight Gain

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When you are pregnant, you need to eat more to help the growth and development of your baby, as well as for the changes in your own body that promote a healthy pregnancy. During at least the last 6 months of pregnancy, you need to eat or drink about 100 more calories per day than you did before you were pregnant.

How much weight you gain during pregnancy depends on your weight before pregnancy (see box). A healthy gain for most women is between 25 and 35 pounds. If you are overweight, you should gain less, but some weight gain is normal. If you are underweight, you should gain more. Talk with your doctor about the amount of weight you can expect to gain. This may vary if you are pregnant with more than one baby. clip_image006

Special Concerns

Vegetarian Diets

If you are a vegetarian, you can continue your diet during your pregnancy. However, you will need to plan your meals with care to ensure you get the nutrients you and your baby need. Be sure you are getting enough protein and that it is the correct type. You will probably need to take supplements, especially iron, vitamin B12, and vitamin D.

Lactose Intolerance

Milk and other dairy products are the best sources of calcium in your diet. Some women have symptoms such as bloating, diarrhea, gas, and indigestion after drinking milk or eating dairy products. This is known as lactose intolerance.

During pregnancy, these symptoms often improve. But if you still have problems after eating or drinking dairy products, talk with your doctor or dietitian. He or she may prescribe calcium supplements if you cannot get enough calcium from other foods. Calcium also can be found in cheese, yogurt, sardines, certain types of salmon, spinach, and fortified orange juice.

Mercury

Fish and shellfish are good sources of protein, omega-3 fatty acids, and other nutrients. However, pregnant women should not eat certain kinds of fish because they contain high levels of a form of mercury that can be harmful to the developing fetus.

You should avoid eating shark, swordfish, king mackerel, or tilefish during pregnancy. These large fish contain high levels of mercury. Albacore tuna also is high in mercury so you may want to choose canned chunk light tuna instead. Other types of fish are fine in limited amounts. You can eat up to 12 ounces (about two meals) of other varied fish and shellfish per week.

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Check local advisories about fish caught in local rivers and streams. If there is no advice about them, it may be safe to eat up to 6 ounces (one meal) per week of fish from local waters. During that week, do not eat any other fish.

Listeriosis

Listeriosis is an illness caused by bacteria that can occur in unpasteurized milk and soft cheese and prepared and uncooked meats, poultry, and shellfish. It can be particularly harmful to pregnant women and their babies.

Symptoms occur several weeks after you eat the food. They can include fevers, chills, muscle aches, and back pain. In some cases, there may be no symptoms at all. When a pregnant woman is infected, the disease can cause miscarriage or stillbirth.

Because the symptoms of listeriosis are like the flu, it can be difficult to diagnose. If you have a fever or flu-like illness, check with your doctor who may take samples from your vagina, cervix, and blood to be checked. If the bacteria are found, you and your baby can be treated with antibiotics. If there is a chance that a newborn is infected, he or she also can be tested and treated.

To prevent listeriosis, wash all fresh fruits and vegetables before using them. While you are pregnant, do not eat:

  • Unpasteurized milk or soft cheeses
  • Raw or undercooked meat, poultry, shellfish
  • Prepared meats, such as hot dogs or deli meats, unless they are reheated until steaming hot

Always be sure to wash your hands and any utensils, countertops, or cutting boards that have been in contact with uncooked meats.

Pica

During pregnancy, some women feel strong urges to eat non-food items such as clay, ice, laundry starch, or cornstarch. This is called pica. Pica can be harmful to your pregnancy. It can affect your intake of nutrients and can lead to constipation and anemia. Talk with your doctor if you have any of these urges. He or she may be able to suggest other things you can do when you feel the urge to eat non-food items.

Finally...

Eating right during your pregnancy is one of the best things you can do for yourself and your baby. Take a look at the foods in your daily diet. Make sure they provide the nutrients you and your baby need. It is never too late to start eating a healthy diet.

PREGNANCY AFTER 35

What you need to know:
Healthy women from age 35 into their 40s usually have healthy pregnancies. If problems do arise, they can usually be successfully treated.

Women over age 35 have an increased risk of:

Because of these increased risks for women over 35, prenatal care is especially important.

What you can do:
No matter what your age, see your health care provider before trying to get pregnant. This is especially important if you:

  • Have a chronic medical condition, such as diabetes, a seizure disorder or high blood pressure
  • Are on long-term medication

If not under control, some medical conditions can cause risks for you and your baby.

If you are older than 35 and don’t get pregnant after trying for six months, see your health care provider.

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A Mommy After 35

Most healthy women from age 35 into their 40s have healthy pregnancies. Most women over 35 are in good health. Good prenatal care and healthy habits can help you reduce certain risks. If problems do arise for women over 35, they can usually be successfully treated.

No matter what your age, see your health care provider before trying to get pregnant if you:

  • Have a chronic medical condition, such as diabetes, a seizure disorder or high blood pressure
  • Are on long-term medication

If not under control, some medical conditions can cause risks for you and your baby.
If you are older than 35 and don’t get pregnant after trying for six months, see your health care provider. Older women may find it harder to get pregnant than younger women because fertility declines with age. In many cases, infertility can be treated.
Prenatal Care Is Important
Prenatal care is especially important for women over 35 because:

  • They’re more likely to get high blood pressure and diabetes for the first time during pregnancy.
  • They may choose to have testing for Down syndrome, a combination of mental retardation and physical defects.

Healthy Habits
To help reduce risks during pregnancy:

  • Eat healthy foods.
  • Gain a healthy amount of weight.
  • Exercise, with your health care provider’s guidance.
  • Don’t drink alcohol, smoke or take illegal drugs.
  • Don’t take any medications or herbal supplements without first checking with your health care provider.

Prenatal Screening Tests
Ask your provider about prenatal screening tests for the baby. For instance, amniocentesis is often recommended for pregnant women 35 or older.
In amniocentesis, the health care provider inserts a thin needle through the woman’s abdomen. A small amount of amniotic fluid (the fluid that surrounds and protects the baby) is removed and tested for chromosomal abnormalities such as Down syndrome or a specific genetic disorder for which the fetus is at risk. Test results are usually available within a week or two. Most women who have prenatal screening tests learn that the baby is healthy and feel reassured by the results.

HUMAN FERTILIZATION

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Human fertilization is the union of a human egg and sperm, usually occurring in the ampulla of the fallopian tube. It is also the initiation of prenatal development. Scientists discovered the dynamics of human fertilization in the nineteenth century.

Fertilization (also known as conception, fecundation and syngamy), is the fusion of gametes to produce a new organism. The process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo.

It is when first of all the acrosome at the head tip produces enzymes, which cuts through the outer jelly coat of the egg. After that has happened, the sperm plasma fuses with the egg’s plasma membrane. Finally, the Head disconnects with the body, and the egg can now travel down the Fallopian tube to reach the womb, where the baby grows.

Fertilization may or may not involve sexual intercourse. In vitro fertilisation (IVF) is a process by which egg cells are fertilized by sperm outside the womb, in vitro. Sperm is propelled through the female reproductive tract by flagellation and may get through the jelly coat through a process called sperm activation. The oocyte and sperm fuse once the sperm is through the corona radiata and the zona pellucida; two layers covering and protecting the oocyte from fertilization by more than one sperm.

Corona radiata

Human ovum examined fresh in the liquor folliculi. The zona pellucida is seen as a thick clear girdle surrounded by the cells of the corona radiata.
The egg itself shows a central granular deutoplasmic area and a peripheral clear layer, and encloses the germinal vesicle, in which is seen the germinal spot.

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The egg binds the sperm through the corona radiata, a layer of follicle cells on the outside of the secondary oocyte. Fertilization is when the nuclei of a sperm and an egg fuse. The successful fusion of gametes form a new organism

Acrosome reaction

The acrosome reaction must occur to mobilise enzymes within the head of the spermatozoon to degrade the zona pellucida.

Zona pellucida

The sperm then reaches the zona pellucida, which is an extra-cellular matrix of glycoproteins. A special complementary molecule on the surface of the sperm head then binds to a ZP3 glycoprotein in the zona pellucida. This binding triggers the acrosome to burst, releasing enzymes that help the sperm get through the zona pellucida.

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Some sperm cells consume their acrosome prematurely on the surface of the egg cell, facilitating for other surrounding sperm cells, having on average 50% genome similarity, to penetrate the egg cell. It may be regarded as a mechanism of kin selection.

Cortical reaction

Once the sperm cells find their way past the zona pellucida, the cortical reaction occurs: cortical granules inside the secondary oocyte fuse with the plasma membrane of the cell, causing enzymes inside these granules to be expelled by exocytosis to the zona pellucida. This in turn causes the glyco-proteins in the zona pellucida to cross-link with each other, making the whole matrix hard and impermeable to sperm. This prevents fertilization of an egg by more than one sperm.

Fusion

The sperm fuses with the oocyte, enabling fusion of their genetic material, in turn.

Cell membranes

The cell membranes of the secondary oocyte and sperm fuse together.

cell membrane
Transformations

Both the oocyte and the sperm go through transformations, as a reaction to the fusion of cell membranes, preparing for the fusion of their genetic material.

The oocyte now completes its second meiotic division. This results in a mature ovum. The nucleus of the oocyte is called a pronucleus in this process, to distinguish it from the nuclei that are the result of fertilization.

Diagram showing the reduction in number of the chromosomes in the process of maturation of the ovum.

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Second meiotic division :

Events involving meiosis, showing chromosomal crossover

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The sperm's tail and mitochondria degenerate with the formation of the male pronucleus. This is why all mitochondria in humans are of maternal origin.

Replication

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The pronuclei migrate toward the center of the oocyte, rapidly replicating their DNA as they do so to prepare the new human for its first mitotic division.

Mitosis

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The male and female pronuclei don't fuse, although their genetic material do so. Instead, their membranes dissolve, leaving no barriers between the male and female chromosomes. During this dissolution, a mitotic spindle forms around them to catch the chromosomes before they get lost in the egg cytoplasm. By subsequently performing a mitosis (which includes pulling of chromatids towards centrioles in anaphase) the cell gathers genetic material from the male and female together. Thus, the first mitosis of the union of sperm and oocyte is the actual fusion of their chromosomes.

Each of the two daughter cells resulting from that mitosis have one replica of each chromatid that was replicated in the previous stage. Thus, they are genetically identical.

In other words, the sperm and oocyte don't fuse into one cell, but into two identical cells.

Monday, June 29, 2009

EPILEPSY and PREGNANCY

Treatment for epilepsy complicating pregnancy

Epilepsy and Pregnancy Increased Risks


General Population

Women with Epilepsy

Major Malformations

2 to 3 Percent

4 to 8 Percent

Minor Malformations

5 to 10 Percent

10 to 15 Percent

Fetal Death

2 to 7 Percent

2 to 14 Percent

More than 90 percent of women with epilepsy will have normal, healthy infants. However, they are at greater risk for complications of pregnancy, labor and adverse pregnancy outcomes than women without epilepsy. Preconceptional counseling and coordination of care among all members of the health care team is key to treating women with epilepsy of reproductive age.

Conception

Fertility

Women with epilepsy have fewer children than women in general, with a fertility rate 25 to 33 percent lower than average. While personal choice and/or societal pressure may play some role in this disparity, research has indicated that women with epilepsy have a higher incidence of menstrual irregularities, polycystic ovarian disease and reproductive endocrine disorders. Any of these may reduce fertility.

Unplanned Pregnancies

Women with epilepsy taking certain anti-epileptic drugs (AEDs) may experience failure of hormonal birth control methods. Some of the medications [carbamazepine, oxcarbazepine, phenytoin, barbiturates (phenobarbital, mephobarbital, and primidone) and topiramate] may lower concentrations of estrogen, thus reducing effectiveness of the hormonal contraceptive.

Congenital Malformations

Major Malformations

Major malformations are defined as defects of medical, surgical or cosmetic importance. This type of anomaly, which will seriously affect a child’s life, occurs in 2 to 3 percent of all liveborn children. For women with epilepsy on one seizure medication, the incidence is estimated to be 4 to 8 percent and possibly greater for women with epilepsy taking more than one drug. Types of major malformations occurring most often in children of women with epilepsy are orofacial clefts, cardiac abnormalities and neural tube defects.

Folic acid supplementation (at a minimum dose of 0.4 mg daily) is especially important prior to conception and during pregnancy in women with epilepsy to lower the risk of neural tube defects in the offspring.

In general, AED polypharmacy and higher blood levels of AEDs are associated with the increased incidence of birth defects in infants born to women with epilepsy. A single AED at the lowest possible dose for efficacy is recommended whenever possible.

Minor Anomalies

The incidence of minor physical defects in infants born to women with epilepsy is approximately 15 percent. Features such as hypertelorism, epicanthal folds, shallow philtrum, distal digital hypoplasia, and simian creases are often present as a familial trait. Although the incidence is reported as 2 to 3 times greater in women with epilepsy, these may be present in infants whose mothers use other types of medication or have excessive alcohol intake during pregnancy. Many of these minor physical defects appear to be idiopathic in nature. These anomalies do not cause any serious problems and are primarily of cosmetic concern.

Other CNS Effects

A greater incidence of mental retardation and/or microcephaly has been reported in children of women with epilepsy, but these studies have been inconsistent and have not always been controlled for other possible contributing factors (such as inherent genetics, and the effects of maternal seizures or AEDs in utero).

However, developmental delays may be significant in terms of risk to infants of women with epilepsy. Factors other than the maternal epilepsy that are thought to be important are IQ scores in the mother and AED polypharmacy (particularly exposure to phenobarbital in utero).

Spontaneous Abortion

There is no increased risk of early fetal death (the not uncommon, spontaneous abortion within the first 20 weeks post-conception) in women with epilepsy. Late fetal loss (a stillbirth or spontaneous abortion after 20 weeks of pregnancy) shows an increased incidence in women with epilepsy, as much as twofold over the general population (2 to 7 percent of all pregnancies and 2 to 14 percent in women with epilepsy, depending on the study).

Anti-epileptic Medications

Concerns

As stated earlier, the risk for adverse effects on the fetus increases when maternal AED polypharmacy is present. All commonly used AEDs have been associated with congenital malformations. Some of the newer AEDs have not been used in large enough numbers to have meaningful data.

Valproic acid (with a risk of 1 to 2 percent), and to a lesser degree, carbamazepine (with a risk of 0.5 percent) have been associated with neural tube defects, specifically spina bifida. Folate supplementation used prior to conception and throughout the childbearing years may minimize this risk.

Many experts believe that trimethadione is contraindicated in women with epilepsy who might become pregnant because it has been associated with a high incidence of fetal loss and congenital malformations.

You may wish to encourage all pregnant women taking AEDs to register with the North American AED Pregnancy Registry housed at Massachusetts General Hospital, Harvard Medical School. The toll free number is (888) 233-2334.

Management

Uncontrolled seizures, particularly generalized tonic-clonic episodes, are hazardous during pregnancy and discontinuing AEDs may pose a greater risk for both mother and fetus than the possible adverse effects of the medication. Miscarriage, trauma related to falls, fetal hypoxia and acidosis are all possible sequelae of maternal seizures.

Status epilepticus carries a high mortality rate for mother and fetus, and generalized seizures occurring during labor can result in fetal bradycardia.

During pregnancy, one quarter to one third of women with epilepsy have an increase in seizure frequency despite continued use of AEDs. Decreased protein binding of AEDs, increased drug clearance, and increased maternal plasma volume during pregnancy may lower serum concentrations of AEDs, requiring more frequent laboratory assessments, and dosage adjustments.

Plasma levels of unbound AEDs should be monitored closely throughout pregnancy and for at least 8 weeks following delivery, as it is common for levels to rise in the postpartum period.

Pregnancy Complications

Other potential obstetrical problems seen more frequently in women with epilepys are hyperemesis, gravidarum, vaginal bleeding, and anemia. Difficulties during labor and delivery include premature labor, failure to progress, and an increased rate of cesarean sections.

Hemorrhagic Disorder of the Newborn

This is a unique hemorrhagic disease of the neonate that occurs in the first 24 hours of life. Maternal AEDs competitively inhibit vitamin K transport across the placenta and the infant has prolonged prothrombin and partial thromboplastin times. The risk can be reduced by maternal supplementation with oral vitamin K (at a dose of 10 mg/ day) during the last month of pregnancy. This specific neonatal disorder seems to be associated with exposure to AEDs in utero (phenobarbital, primidone, phenytoin, and perhaps others).

Risk of Seizures in the Child

There is a higher risk for women with epilepsy to have children with the condition than for men with epilepsy. Seizure type and age of onset also affect incidence of epilepsy in the child. It is encouraging to recognize that even for patients in the highest risk groups, the risk that an offspring will develop epilepsy is less than 10 percent. Also see Genetics.

REFERENCES

  1. Holmes LB, Harvey EA, Coull BA, et al. The teratogenicity of anticonvulsant drugs. NEJM. 2001;344(15):1132-1138.
  2. Yerby M. Treatment of epilepsy during pregnancy. In: Wyllie E, ed. The Treatment of Epilepsy, Second Edition. Baltimore: Williams & Wilkins; 1996:785-798.
  3. Practice parameter: management issues for women with epilepsy (summary statement). Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology. 1998;51:944-8.
  4. Seizure disorders in pregnancy. In: ACOG Educational Bulletin. Washington, DC: American College of Obstetricians and Gynecologists; 1996:231.

GENITAL HERPES and PREGNANCY

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Most women with genital herpes give birth to healthy babies. However, if you suffer from genital herpes there is a very small risk that your baby will catch the infection and if she does the results can be serious, even fatal. That's why it is important to tell your midwife if you or your partner have ever had an outbreak of genital herpes or if you think you have any of the symptoms. Extra care can then be taken of you and your baby.

What is genital herpes?

Genital herpes is caused by the herpes simplex virus which also causes cold sores around and in the mouth. Genital herpes is usually caused by herpes simplex virus type 2 (HSV-2), while cold sores are usually caused by herpes simplex virus type 1 (HSV-1). However, genital herpes can also be caused by HSV-1. Once you have been infected with a herpes virus it stays in your body for life, only becoming active every now and again.

How might genital herpes affect my pregnancy?

If you had genital herpes before you became pregnant then the risk of your baby becoming infected is very low, even if you have an outbreak during your pregnancy or during labour. This is because your body has had time to develop antibodies to the herpes simplex virus and this immunity is passed on to your baby during pregnancy. Your baby will continue to be immune for up to three months after the birth.
If you catch genital herpes for the first time in the first or second trimester of your pregnancy, there is a slight risk that it will affect your developing baby. The infection has been linked to miscarriage, intrauterine growth retardation (IUGR), premature labour, microcephaly (where the baby's brain is underdeveloped) and hydrocephaly (where fluid builds up around the baby's brain) but this happens very rarely. Your doctor will probably refer you to a genitourinary medicine (GUM) clinic where you will be given a 5-day course of an oral antiviral medicine, usually acyclovir. The acyclovir will help to reduce your discomfort and speed up the healing or your sores. It is safe to use in pregnancy.
Your baby is at greater risk if you catch genital herpes for the first time in late pregnancy before you have had time to develop antibodies to the virus and to pass this immunity on to your baby. Your baby can catch the virus through direct contact with an active sore, which is weeping or inflamed, during birth. If a baby catches the infection at birth it is called neonatal herpes. About four in ten babies develop neonatal herpes when born vaginally to women with a first infection when they come to give birth.
In the UK, only one or two babies in 100,000 catch neonatal herpes, but it can be very serious and even fatal. Neonatal herpes can cause infection in a baby's skin, eyes or mouth and may damage the brain or other organs. If your baby does catch neonatal herpes, effective treatment with antiviral medicine for you and your baby can help prevent and minimise long term damage to your baby's health.

Will I need to have a caesarean?

If you suspect you have an active genital herpes infection in the last trimester of pregnancy it is vital that you tell your midwife or doctor. If you have never had herpes before then you will probably be advised to have a planned caesarean section, particularly if you have your first outbreak in the last six weeks of pregnancy. This is to minimise the risk of transmitting the virus to your baby.
If you want to go ahead with a vaginal delivery, then your obstetrician will try to avoid any invasive procedures such as ventouse or forceps and will give you intravenous acyclovir during labour and delivery as this may reduce the risk of your baby catching herpes. Your newborn baby will also be given acyclovir.
If it is not your first infection, you will probably be given acyclovir daily for the last four weeks of pregnancy. You will not be advised to have a caesarean as your baby will probably have immunity to the virus.

Can I breastfeed if I have herpes?

The herpes virus is not transmitted through breastmilk so having herpes shouldn't stop you from breastfeeding, providing you don't have any sores on your breasts. Make sure that sores elsewhere on your body are covered and wash your hands frequently and carefully. If you are taking acyclovir, it will be excreted in your breastmilk but is not thought to be harmful.

What are the symptoms of a genital herpes infection?

Symptoms vary a lot from person to person. What most people do find is that symptoms are usually worse, and last longer, the first time they have a herpes outbreak. Symptoms of a primary or first infection may include:
• painful sores over your genitals and buttocks
• itching
• stinging when passing urine
vaginal discharge
• swollen glands in the groin area
• flu-like symptoms including fever, headache and muscle aches
A primary episode can last two to three weeks.
With a second or later infection you may get no symptoms at all or just a small area of irritation. If it is not your first outbreak, it will probably be over within three to five days.
Whether or not you have symptoms, it is important to remember that you are still contagious during a herpes recurrence. In fact, most infections occur when the person passing it on has no noticeable symptoms. This is why it is important to tell your midwife if you or your partner suspect you may have had a herpes outbreak in the past.

How can I avoid catching the virus while I am pregnant?

If your partner has genital herpes you need to be particularly careful when you are pregnant. As the virus can be transmitted without your partner knowing that he is having an outbreak there are no foolproof methods to avoid catching herpes. In fact, the virus is most infectious when, or just before, symptoms appear. You can catch herpes from penetrative and non-penetrative sex (vaginal or anal), from oral sex, and by sharing sex toys. Condoms may help to reduce the risk of catching herpes from your partner, or you may want to avoid sex altogether. You should also be aware that you can catch genital herpes from your partner if he has oral herpes and performs oral sex.

Who can help?

Talk to your GP or midwife or contact the Herpes Viruses Association for more information.

CHICKENPOX and PREGNANCY

Effects of Chicken Pox on the Pregnant Woman and her Unborn Child

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Chicken pox is usually a benign, self-limited, viral infection caused by the varicella virus. However, chicken pox acquired during pregnancy causes an increase risk of complications to the mother and the infant. The time of infection, during early pregnancy or near delivery, determines the risk to mother and child.

Pregnant Women Exposed to Chicken Pox
Pregnant women who have a history of a previous chicken pox infection or who have been immunized have antibodies to the virus. These antibodies are transferred to the infant through the placenta throughout the pregnancy. Therefore, pregnant women who are immune and are exposed to someone with chicken pox do not need to worry about complications for themselves or their infant.

Testing for Immunity in Pregnancy
All women should be questioned about previous chicken pox infection or immunization at their first prenatal visit. Of those women who do not remember a past infection or immunization, 80% to 90% have antibodies and are considered immune. For this reason, testing for antibodies is controversial, but many practitioners obtain this test at the first prenatal visit.

Maternal Complications of Chicken Pox in Pregnancy
A primary chicken pox infection occurs in only 0.05% to 0.07% of pregnancies because most women of childbearing age have immunity to the varicella virus because of a previous infection or immunization. Women who do acquire chicken pox while pregnant, especially in the third trimester, are at a greater risk of developing varicella pneumonia. Varicella pneumonia is a potentially life-threatening infection of the lungs by the varicella virus.

Infant Complications of Chicken Pox in Early Pregnancy
Primary chicken pox infection in the first trimester of pregnancy, especially weeks 8 to 12, carries a 2.2% risk of congenital varicella syndrome, a syndrome of birth defects in the infant. The most common manifestation of congenital varicella syndrome is scarring of the skin. Other abnormalities that can occur include a smaller than normal head, eye problems, low birth weight, small limbs, and mental retardation.

Infant Complications of Chicken Pox in Late Pregnancy
If a woman acquires a primary chicken pox infection within 5 days before and 2 days after delivery, her newborn is at risk for disseminated varicella infection. Disseminated varicella infection occurs when the virus infects a newborn before the transfer of protective maternal antibodies. This overwhelming viral infection leads to death in 25% of cases.

Treatment of Pregnant Women with Chicken Pox
Women who acquire primary chicken pox during pregnancy should be treated with the antiviral drug acyclovir (Zovirax) which seems to be safe in pregnancy. Pregnant women with varicella pneumonia should be treated with IV acyclovir and be observed in the hospital. In addition women who are not immune to varicella, but are exposed may be treated with varicella-zoster immunoglobulin (VZIG), a substance that triggers an immune response against the varicella virus.

Treatment of Infants with Chicken Pox
Infants whose mothers develop varicella 5 days before delivery or 2 days following delivery should receive VZIG after birth. Infants who develop varicella during the first 2 weeks of life should be treated with IV acyclovir.

SMOKING and PREGNANCY

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Smoking is a major public health problem. All smokers face an increased risk of lung cancer, other lung diseases, and cardiovascular and other disorders. Smoking during pregnancy can harm the health of both a woman and her unborn baby. Currently, at least 10 percent of women in the United States smoke during pregnancy. (1)
In the United States and in other industrialized countries, 18 percent of women smoke.(2) This proportion is somewhat smaller in developing countries where only 8 percent of women smoke.(3) Statistics from the United States are compelling. According to the U.S. Public Health Service (4) , if all pregnant women in this country stopped smoking, there would be an estimated:

  • 11 percent reduction in stillbirths
  • 5 percent reduction in newborn deaths

Cigarette smoke contains more than 2,500 chemicals. It is not known for certain which of these chemicals are harmful to the developing baby, but both nicotine and carbon monoxide play a role in causing adverse pregnancy outcomes.

How can smoking harm the newborn?
Smoking nearly doubles a woman's risk of having a low-birthweight baby. In 2004, 11.9 percent of babies born to smokers in the United States were of low birthweight (less than 5½ pounds), compared to 7.2 percent of babies of nonsmokers (1). Low birthweight can result from poor growth before birth, preterm delivery or a combination of both. Smoking has long been known to slow fetal growth. Smoking also increases the risk of preterm delivery (before 37 weeks of gestation) (5). Premature and low-birthweight babies face an increased risk of serious health problems during the newborn period, chronic lifelong disabilities (such as cerebral palsy, mental retardation and learning problems), and even death.

The more a pregnant woman smokes, the greater her risk of having a low-birthweight baby. However, if a woman stops smoking even by the end of her second trimester of pregnancy, she is no more likely to have a low-birthweight baby than a woman who never smoked (6).
A recent study suggests that women who smoke anytime during the month before pregnancy to the end of the first trimester are more likely to have a baby with birth defects, particularly congenital heart defects (7) . The risk of heart defects appears to increase with the number of cigarettes a woman smokes.

Can smoking cause pregnancy complications?
Smoking is associated with a number of pregnancy complications. Smoking cigarettes doubles a woman's risk of developing placental problems (4) . These include:

  • Placenta previa (a low-lying placenta that covers part or all of the opening of the uterus)
  • Placental abruption (in which the placenta peels away, partially or almost completely, from the uterine wall before delivery)

Both can result in heavy bleeding during delivery that can endanger mother and baby, although cesarean delivery can prevent most deaths.

Smoking in pregnancy increases a woman's risk of premature rupture of the membranes (PROM), when the sac that holds the baby inside the uterus breaks before completion of 37 weeks of pregnancy (4) . (Usually, when it breaks, normal labor ensues within a few hours.) If the rupture occurs before 37 weeks of pregnancy, it often results in the birth of a premature baby.

Does smoking affect fertility?
Cigarette smoking can cause reproductive problems before a woman even becomes pregnant. Studies show that women who smoke may have more trouble conceiving than nonsmokers (4) . Studies suggest that fertility returns to normal after a woman stops smoking.

Does smoking during pregnancy cause other problems in babies or young children?
A 2003 study suggests that babies of mothers who smoke during pregnancy undergo withdrawal-like symptoms similar to those seen in babies of mothers who use some illicit drugs (8) . For example, babies of smokers appear to be more jittery and difficult to soothe than babies of nonsmokers.

Babies whose mothers smoked during pregnancy are up to three times as likely to die from sudden infant death syndrome (SIDS) as babies of nonsmokers (5) .

Studies suggest that babies of women who are regularly exposed to secondhand smoke during pregnancy may have reduced growth and may be more likely to be born with low birthweight (5). Pregnant women should avoid exposure to other people's smoke.

How can a woman stop smoking?
The March of Dimes recommends that women stop smoking before they become pregnant and do not smoke throughout pregnancy and after the baby is born. A woman's health care provider can refer her to a smoking-cessation program or suggest other ways to help her quit. The March of Dimes supports a 5- to 15-minute, 5-step counseling approach called “The 5 A's,” which is performed by the health care provider during routine prenatal visits. This approach has been shown to improve smoking cessation rates among pregnant women by at least 30 percent .

Studies suggest that certain factors make it more likely that a woman will be successful in her efforts to quit smoking during pregnancy. These include:

  • Attempting to quit in the past
  • Having a partner who doesn't smoke
  • Getting support from family or other important people in her life
  • Understanding the harmful effects of smoking

How does exposure to smoke after birth affect a baby?
It is important to stay smoke-free after the baby is born. Parents should refrain from smoking in the home and should ask visitors to do the same. Babies who are exposed to smoke suffer from more lower-respiratory illnesses (such as bronchitis and pneumonia) and ear infections than do other babies. Babies who are exposed to their parents' smoke after birth also may face an increased risk of asthma and SIDS.

Smoking harms a mother's health, too. Smokers have an increased risk of lung and other cancers, heart disease, stroke and emphysema (a potentially disabling and, sometimes, deadly lung condition). Quitting smoking makes parents healthier and better role models for their children.

Does the March of Dimes fund research on the risks of smoking during pregnancy?
The March of Dimes has long supported research on the risks of smoking during pregnancy. In the 1970s, March of Dimes-supported research suggested that nicotine and carbon monoxide reduce the supply of oxygen to the baby, perhaps explaining how these chemicals in cigarette smoke reduce fetal growth.

In 2002, a March of Dimes grantee published a study that may shed light on why some women who smoke cigarettes during pregnancy have low-birthweight babies and others do not (10) . The researcher reported that pregnant women who smoke are more likely to have a premature or low-birthweight baby if they have either of two common genetic traits (which influence the body's ability to dispose of certain chemicals). These findings could lead to better ways to identify and treat women at high risk of having a low-birthweight baby.

A current March of Dimes grantee is investigating whether smoking at a critical stage of embryonic palate development increases the risk of cleft lip/palate.

What resources are available for health care providers?

References

  1. Martin, J.A., et al. Births: Final Data for 2004. National Vital Statistics Reports, volume 55, number 1, September 29, 2006.
  2. Centers for Disease Control and Prevention (CDC). Smoking and Tobacco Fact Sheet: Women and Smoking. February 28, 2007.
  3. World Health Organization (WHO). Women and the Tobacco Epidemic: Challenges for the 21st Century. 2001.
  4. U.S. Department of Health and Human Services. The Health Consequences of Smoking: A Report of the Surgeon General, 2004. Centers for Disease Control and Prevention, Office on Smoking and Health, Atlanta Georgia, May 2004.
  5. Centers for Disease Control and Prevention (CDC). What Do We Know About Tobacco Use and Pregnancy. June 11, 2007.
  6. American College of Obstetricians and Gynecologists (ACOG). Smoking Cessation during Pregnancy. ACOG Committee Opinion, number 316, October 2005.
  7. Malik, S., et al. Maternal Smoking and Congenital Heart Defects. Pediatrics, volume 121, number 4, April 2008, pages e810-e816.
  8. Law, K.L., et al. Smoking During Pregnancy and Newborn Neurobehavior. Pediatrics, volume 111, number 6, June 2003, pages 1318-1323.
  9. Centers for Disease Control and Prevention (CDC). Preventing Smoking During Pregnancy. November 2005.
  10. Wang, X., et al. Maternal Cigarette Smoking, Metabolic Gene Polymorphism, and Infant Birth Weight. Journal of the American Medical Association, volume 287, number 2, January 9, 2002, pages 195-202.