Also indexed as: Alcohol-Related Birth Defects, Alcohol-Related
Neurodevelopmental Disorder, Anencephaly, Cleft Lip, Cleft Palate, Fetal Alcohol Syndrome,
Heart Defects, Limb-Reduction Defects, Microcephaly, Neural Tube Defects, Spina Bifida,
Urinary Tract Defects
Give your baby the best chance at being born strong and healthy.
Start by gathering vital information before you get pregnant. According to research or other
evidence, the following self-care steps may be helpful:
- Take vitamins in advance
- To help prevent neural tube and other birth defects, start taking
a daily multivitamin months before getting pregnant and continue through your pregnancy; look
for brands with at least 400 mcg of folic acid and 15 mg of zinc
- Don’t drink alcohol
- Protect your baby from a variety of serious birth defects and
developmental disorders by avoiding alcohol while you’re pregnant
- Keep an eye on vitamin A
- Check with your healthcare practitioner before taking supplements
that contain more than 10,000 IU of vitamin A
- Cut the caffeine
- Reduce the risk of miscarriage by avoiding caffeinated coffee,
tea, and soft drinks
- Avoid too much noise
- Stay away from noisy workplace environments, loud music, and
airport jet traffic to protect your baby’s fragile ears and hearing
- Check your supplement safety
- Talk with your healthcare provider to make sure all your
medications and supplements are safe to take during pregnancy
These recommendations are not comprehensive and are not intended to replace
the advice of your doctor or pharmacist. Continue reading the full birth defects article for
more in-depth, fully-referenced information on medicines, vitamins, herbs, and dietary and
lifestyle changes that may be helpful.
About birth defects
Birth defects affect about 120,000 babies born in the United States each year. Birth
defects account for more than 20% of infant deaths and contribute substantially to life-long
disabilities.
The causes of about 70% of all birth defects are unknown. Various occupational hazards,
dietary factors, medications, personal habits, and environmental exposures may contribute to
birth defects, but many questions remain about the exact nature of their influence.
Neural tube defects (NTDs) are one of the most common birth defects. NTDs result when the
neural tube (which includes the spinal cord and brain) fails to close during the first month
of embryonic development. NTDs include several disorders ranging from spina bifida (incomplete
closure of the bones around the spinal cord that can lead to paralysis) to a lack of a cranium
(the bones of the head) and its contents, called anencephaly. Approximately 4,000 pregnancies
in the United States are affected by NTDs each year.
Product ratings for birth
defects
Dietary changes that may be helpful
Drinking beverages containing caffeine may
increase the risk of miscarriage among non-smoking women, according to one study.1
Women who miscarried during the first 12 weeks of pregnancy were found to have significantly
higher consumption of caffeine compared with women who carried their pregnancies to term. This
association was limited to women who did not smoke cigarettes. Non-smoking women who consumed
500 mg of caffeine per day, or roughly five cups of coffee, were twice as likely to suffer a miscarriage
compared with women who drank less than one cup of coffee per day. An increased risk of
miscarriage was also found in women consuming as little of 100 mg of caffeine per day. This
finding appears to indicate that there may be no “safe” amount of regular caffeine
consumption during pregnancy.
One cup of coffee contains roughly 100 mg of caffeine, depending on how it is brewed (drip
coffee contains the most caffeine and instant coffee the least). Black tea contains about 40–70 mg per cup, and a
12-oz. can of caffeinated soda may contain
30–55 mg of caffeine. Caffeine is also found in cocoa, chocolate, and certain
over-the-counter medications.
Lifestyle changes that may be helpful
Pregnant women should avoid alcohol completely. Alcohol intake by pregnant women can lead
to a spectrum of disorders, including fetal alcohol syndrome (FAS), alcohol-related
neurodevelopmental disorder (ARND), and alcohol-related birth defects (ARBD). FAS is
characterized by growth retardation, abnormal facial features, and mental retardation. In
addition, about 80% of children with FAS have an abnormally small cranium, called
microcephaly. Children with FAS also have serious lifelong disabilities, including learning
disabilities and behavioral problems.2 3 4 ARND and ARBD are
milder versions of FAS.5
Drinking just one alcoholic beverage per day while pregnant has been associated with
increased risk of having a child with impaired growth. The potential for harm increases as
larger amounts of alcohol are consumed. Even minimal alcohol consumption during pregnancy can
increase the risk of hyperactivity, attention deficiency, and emotional problems in the
child.6 No safe level of alcohol intake during pregnancy has been
determined.7 8
There are many medications that a woman should not use during pregnancy. A healthcare
practitioner should review all over-the-counter and prescription medications, as well as any
nutritional or herbal supplements. For example, the commonly prescribed acne medication, isotretinoin (Accutane®), a synthetic form
of vitamin A, can cause severe birth defects if used during pregnancy.
Excessive noise may have damaging effects on a developing fetus. Many pregnant women are
exposed to noise in the workplace.9 10 In one study, the children of
women exposed consistently to high levels of occupational noise during pregnancy were more
likely to have high-frequency hearing loss (identified at four to ten years of age) than were
children whose mothers were not exposed to such noise.11 Noise exposure at these
excessive levels (i.e., 85 to 90 decibels) occurs in many occupations, even among women
wearing protective hearing devices. Other environmental sources of excessive noise include
rock concerts, boom boxes, car stereos, and airport jet traffic.
Women who are obese prior to pregnancy are
at increased risk of having an NTD-affected pregnancy. One study showed a twofold or greater
risk of NTD-affected pregnancy among women who were obese.12
Vitamins that may be helpful
Several studies and clinical trials have shown that 50% or more of NTDs can be prevented if
women consume a folic acid-containing
supplement before and during the early weeks of pregnancy.13 14 The
United States Department of Public Health, the Centers for Disease Control and Prevention
(CDC), and the March of Dimes recommend that all women who are capable of becoming pregnant
supplement with 400 mcg folic acid daily. Daily supplementation prior to pregnancy is
necessary because most pregnancies in the United States are unplanned15 and the
protective effect of folic acid occurs in the first four weeks of fetal
development,16 before most women know they are pregnant.
For women who have had a previous NTD-affected pregnancy, the CDC recommends daily
supplementation with 4,000 mcg per day of folic acid. In a preliminary study, this amount of
supplemental folic acid before and during early pregnancy resulted in a 71% reduction in the
recurrence rate of NTDs.17
In a preliminary study of California mothers, those who had higher intakes of choline during the three months prior to conception
were significantly less likely to give birth to a child with an NTD, compared with women with
lower choline intakes.18 The possibility that choline may protect against NTDs is
plausible, as choline has similar biochemical effects as folic acid, which is known to reduce
NTD risk.
In a preliminary study, women with the highest total dietary zinc intake before pregnancy (including zinc from both
food and supplements) had a 35% decreased risk of having an NTD-affected
pregnancy.19 However, another preliminary study found no association between blood
levels of zinc in pregnant women and the incidence of NTDs.20 Zinc supplementation
(15 mg per day) is considered safe for pregnant women. Given its safety and potential role in
preventing NTDs, a zinc-containing multivitamin is recommended by many doctors to all women of
childbearing age who may become pregnant.
Use of a multivitamin supplement during the
periconceptional period (defined as from the three months prior to pregnancy to the third
month of pregnancy) can contribute significantly to a healthy pregnancy. Use of a multivitamin
during these crucial months of fetal development has been associated with a reduced occurrence
of many birth defects. In a preliminary study, periconceptional use of a multivitamin was
associated with a lowered risk of heart defects in the offspring.21 This
association was not evident when use of the multivitamin began after the first month
of pregnancy. The authors of this study concluded that approximately one in four major heart
defects could be prevented by periconceptional multivitamin use. In another preliminary study,
periconceptional use of a multivitamin was associated with a 43% reduction in the risk of
having an infant with a severe heart defect.22
In a double-blind trial, women given a multivitamin containing folic acid starting at least
one month before becoming pregnant to at least the second month of pregnancy were much less
likely to have a child with a birth defect than were women given a trace mineral
supplement.23 The greatest reduction in risk was seen in the occurrence of urinary
tract defects and heart defects. A preliminary study found that periconceptional use of a
multivitamin reduced the risk for urinary tract defects and limb defects.24 When
multivitamin use was begun after the periconceptional period, there was a reduction in risk
noted for cleft palate and again for urinary tract defects.
Childhood brain tumor rates may also be reduced by a mother’s intake of a
multivitamin while pregnant. In a preliminary study, use of a multivitamin by women for at
least two-thirds of their pregnancy was associated with a decreased risk of brain tumor in the
offspring compared to women who took a multivitamin for less than two-thirds of the
pregnancy.25 The greatest reduction of brain tumor risk (about 50%) was among
children whose mothers took a multivitamin throughout the entire pregnancy.
A preliminary study, published in 1995 in the New England Journal of Medicine
(NEJM),26 concluded that supplementation with more than 10,000 IU (3,000 mcg)
per day of vitamin A can increase the risk of
certain birth defects. Since the publication of that report, women who are or could become
pregnant have been told by doctors to consume no more than 10,000 IU per day of supplemental
vitamin A. However, another study has challenged the findings of the NEJM report. In
the new study, pregnancy outcome was determined in several hundred women who had consumed
10,000 to 300,000 IU (averaging about 50,000 IU) of supplemental vitamin A per day during
early pregnancy.27 No birth defects occurred in any of the infants exposed to
maternal intakes of vitamin A greater than 50,000 IU per day. In fact, when compared with
infants not exposed to vitamin A, a 50% decreased risk for birth defects was found in
this high-exposure group.
A closer look at the recent study reveals a 32% higher-than-expected risk of birth defects
in infants exposed to 10,000 to 40,000 IU of vitamin A per day but, paradoxically, a 37%
decreased risk for those exposed to even higher levels. This suggests that both
“higher” and “lower” risks may have been due to chance. At present,
the level at which birth defects might be caused by vitamin A supplementation is not known,
though it may well be higher than 10,000 IU per day. Nevertheless, women who are pregnant
should talk with a doctor before supplementing with more than 10,000 IU per day.
Are there any side effects or interactions?
Refer to the individual supplement for information about any side effects or interactions.
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