Will Too Much Vitamin B-6 Cause Birth Defects?

Overdosing on vitamin B-6 supplements can potentially cause nerve damage and birth defects for your unborn child -- as well as for health risks for you. However, it is important for pregnant women to get enough dietary B-6, since a B-6 deficiency can also cause birth defects.

Pregnant woman having ultra sound. (Image: Photodisc/Photodisc/Getty Images)

B-6 and Pregnancy

According to the Baby Center, vitamin B-6, also called pyridoxine, is essential for your baby's brain and nervous system development. B-6 is important for people at any age, since your body needs it to metabolize energy from food, make new red and white blood cells and maintain a healthy nervous system. A vitamin B-6 deficiency while you are pregnant can keep your baby's brain from developing correctly, leading to symptoms that can include seizures after birth.

B-6 Overdose

Vitamin B-6 supplements are commonly used to relieve morning sickness for pregnant mothers, but large amounts of B-6 can cause some physical and mental development problems in babies. During the first trimester, taking more than 100 mg of vitamin B-6 can cause physical defects affecting your baby's arms and legs, as well as nerve damage. In addition, excessive daily usage of B-6 supplements may cause your baby to become addicted, causing withdrawal type symptoms after birth. However, the small amounts of B-6 used to treat morning sickness are usually safe.

Amounts

As a pregnant woman, you should aim for around 1.9 mg of vitamin B-6 intake daily, and 2.0 mg while breastfeeding. The Baby Center does say that you do not have to eat this strict amount daily, but can aim for this as an average over a period of a few days. You should beware of supplements with large dosages, like 100 mg or higher; however, lower doses of around 25 mg -- like those used to treat morning sickness -- may be less harmful. Regardless, you should still consult with your doctor before beginning a vitamin B-6 supplement or regimen.

Dietary Sources

The Linus Pauling Institute reports that it is almost impossible to get too much B-6 through your diet, since overdosing usually only occurs when taking supplements. Good natural sources of the vitamin include whole grains and products made from whole grains, potatoes, chicken, turkey, spinach, milk and milk products. Fortified foods, like breakfast cereal, breads and some yogurts, can also have added B-6. It is important to eat a well-balanced diet, with varied sources of B-6 and other nutrients essential for your pregnancy.