Light Drinking While Pregnant: Fine or Foolish?

By Nicholas Staropoli — Oct 13, 2015
Pregnant women are often told that in the late term they're allowed to lightly consume alcohol, But is there any science-based evidence supporting this position? In a recent medical journal article, three experts debate the questions on whether pregnant women should drink, and if so, how much.

Pregnant!Pregnant women are bombarded with health information about their upcoming arrival. Prenatal vitamins, birth plans, eat this, do this, avoid that, sleep like this, etc. etc. The list goes on, ad nauseam. But how much of the advice is true or based in sound science?

Now, with respect to alcoholic consumption, a recent article published in The British Medical Journal featured scientists debating the best way for pregnant women to address this inconclusive topic.

Mary Mather, a retired pediatrician, and Kate Wiles a doctoral research fellow, argued that pregnant women should completely abstain from alcohol. Patrick O Brien, a lecturer in obstetrics and gynecology, took the the position that women should have more autonomy than simply being told not to drink at all.

In the abstinence-only corner, Mather and Wiles presented evidence for alcohol's influence in disrupting fetal development. They pointed out that 4,000 published papers have shown that alcohol is a powerful teratogen -- an agent that can cause birth defects -- and that worldwide, one percent of all births are effected by prenatal alcohol use.

They went on to explain that, "[t]eratogenicity has been conclusively shown in clinical, behavioural, and epidemiological studies, and undisputed teratogenic effects include fetal alcohol syndrome, mental retardation, a spectrum of developmental and behavioural abnormalities, and low birth weight."

However, these statements are not controversial, nor are the findings novel. Fetal-alcohol syndrome is a well established condition. Most medical and public health organizations recommend against women consuming alcohol during pregnancy. But these recommendations are taken as just that -- a suggestion -- and some health organizations state that light drinking, late in pregnancy, is acceptable.

It is this concept that, according to Mather and Wiles, needs to be corrected. They say that there's really no evidence that light or moderate drinking is safe for women. Furthermore, there is no legitimate evidence that alcohol is beneficial to the fetus.

Also, the term "unit" of alcohol (the difference between size and type) which is invoked to provide guidance, is confusing and that it unknowingly contributes to excessive consumption during pregnancy. In short, the opinion expressed by Mather and Wiles is: If there's no benefit, yet huge risk, why drink at all?

O Brien, offering the competing view, did not dispute the claim that alcohol is a teratogen, or dangerous. However, he believes women, as intelligent and autonomous beings, have the ability to hear the evidence and decide for themselves.

He agrees there's too much disagreement, as well as conflicting evidence on the issue. But he believes physicians are responsible for clearing up the ambiguity and presenting the data to women in a clear and concise way. Even when the data are conflicting, O'Brien said, it should be presented as such. He states that we all deal with uncertainty on a daily basis, and making decisions in regard to this issue is no different.

O'Brien added that just because there is uncertainty, that doesn't mean we should abrogate our responsibility by advising to abstain. However, in a way, physicians and health care officials are abrogating responsibility by not answering the question more definitively. It is the duty of physicians and health care organizations to do just that.

Mather and Wiles are advocating for the precautionary principle. However, in this scenario, where prenatal consumption of alcohol clearly provides no benefit to the fetus, then why introduce the risk?