What is the most common type of preventable birth defect?

See below: Neural tube defects (ntds): preventable with pre-pregnancy and ante-natal folic acid fetal alcohol syndrome (fas): avoid alcohol intake when trying to conceive and during pregnancy birth defects caused by medications and other substances some of the cardiac defects may be preventable by avoiding maternal obesity.

Cardiac, neural tube: Cardiac and neural tube defects (including the lethal anencephaly) can be prevented by 75-95% respecively when the woman is on high-dose Folic Acid supplementation preconceptionally. That's why it is vitally important that all reproductive age women take 1-5 mg of folate (folic acid) daily until permanent sterilization. 50% of us pregnancies are unplanned! do not drink alcohol, maintain healthy weight 4 height.

Fetal Alcohol effect: I would have to go with fetal alcohol effects. Though some lay press now say drinking in small amounts during pregnancy as ok, it is not. The developing fetus converts alcohol to formaldehyde, which interferes with any tissue nearby. In large quantities it does produce heart defects & alters facial features.In smaller amounts it can trigger add/adhd. There are tens of thousands affected yearly.

The most common: Preventable cause of intellectual disability is prenatal exposure to alcohol. Since the brain starts forming 3 weeks after conception, it is best not to drink alcohol when planning a pregnancy. The other doctors gave specific advice about reducing the risk of neural tube defects. Women of child-bearing age should take folate (folic acid) daily, so that they are taking it at least 3 months before conception.

I'll weigh in: By far the most preventable cause of prenatal problem is alcohol or tobacco use in a woman of child bearing age. I agree with drs ferguson and fricke.