*According to an economist.
In her new book Expecting Better, economist and new mom Emily Oster parses the evidence behind all the recommendations given to pregnant women. She argues that, as an economist, she's trained to both examine evidence and think about trade-offs.
Oster is the guest on today's show, which we'll post shortly. In the meantime, here are a few of her findings in the book:
There is no question that very heavy drinking during pregnancy is bad for your baby. ... However, this does not directly imply that light or occasional drinking is a problem. ... The bottom line is that the evidence overwhelmingly shows that light drinking is fine. In fact, there is virtually no evidence that drinking a glass of wine a day has negative impacts on pregnancy or child outcomes.
On Weight Gain
The evidence was strong enough to convince me that weight gain does matter in the sense that it impacts the baby's size in particular. But that wasn't quite the same as convincing me that the weekly haranguing [at the doctor's office] was appropriate. How should I think about the downside to gaining too much weight? How should I trade that off against the fact that, let's face it, I was hungry and I like cookies.
The one overwhelming thing I took away from this was that it doesn't matter very much. Gaining a few pounds, even 10 or 15, over the weight limit is not very important. Even in studies that do find some risks to too much weight gain, these effects are small and don't kick in for women who gain, say, 37 pounds. At one visit I was informed that if I continued my current rate of gaining, I would be at 36 pounds, and the limit was 35, so I should try to cut down. Nothing — not evidence and not basic logic — supports this.
I ultimately concluded that the weight of the evidence didn't support limiting my consumption very much. I decided the 3 to 4 cups a day I was having was fine. It's possible you will read this evidence and decide that you would like to stay under 2 cups. There's no reason to have less than that if you feel up to it.