Cross-posted at Fussbucket

New research from Britain shows that light drinking of alcohol during pregnancy may not cause harm and that drinking caffeine might have an effect on birth weight. According to this article in the LA Times, both studies are the largest and most rigorous studies on low levels of alcohol or caffeine to date.

In the alcohol study, researchers conducted in-person interviews with 12,495 new moms whose babies were 9 months old. Women were asked if they drank during their pregnancy and, if so, how much. At 3 years, children were assessed for inappropriate conduct (atypical hitting, arguing and acting out) and cognitive ability (knowing numbers and letters, and naming colors and shapes).

Not surprisingly, outcomes were not good for children whose moms drank heavily while pregnant. But children of light-drinking moms had fewer behavioral or cognitive problems than those of abstinent moms, the article says.

This is good news to me. I did not completely abstain from alcohol during either one of my pregnancies. I drank rarely and very lightly - usually a half glass of wine with a special meal, probably less than ten times during my second and third trimesters. I didn't drink during the first trimester, though.

The study, published online in October in the International Journal of Epidemiology, defined light drinking as not more than two drinks (a 4-fluid-ounce glass of wine or 10 fluid ounces of weak beer) on a single occasion and not more than two occasions per week. No difference was seen between women who drank once or twice during their pregnancies and those who regularly enjoyed a weekend glass of wine.

In the U.S., the American College of Obstetricians and Gynecologists advises pregnant women to avoid alcohol entirely.

The news for caffeine is different. In a study of 2,635 mothers-to-be published online this month in the British Medical Journal, researchers saw effects on babies' birth weights when expectant moms consumed daily doses of as low as 100 mg -- the amount in an 8-ounce cup of coffee. Babies born to women consuming more than 200 mg of caffeine a day weighed an average 2.2 ounces less than those born to moms taking in less than 100 mg. More than 300 mg per day led to a 5-ounce average reduction in birth weight.

A few ounces are not a big deal in otherwise healthy, full-term babies, says lead study author Dr. Justin Konje, a professor of obstetrics and gynecology at the University of Leicester, and are less than the deficits seen in babies of smokers. But in very small infants (say, 2 pounds), 5 ounces may significantly affect the baby's health, the article says.

In the U.S., the March of Dimes says caffeine should be limited to 200 mg per day, based on a study of 1,063 pregnant women by Kaiser Permanente researchers. It found that the risk of miscarriage doubled in women who consumed more than 200 mg, compared with those who consumed little to no caffeine.

With the blessing of my OB, I drank coffee every morning of both my pregnancies. My babies were born huge, but if they'd been preemies it might have been a different story.

Did you drink alcohol or caffeine while pregnant? What do you think of this latest research?