Oster’s conclusions about the quantities of alcohol and caffeine that can be consumed safely in pregnancy—a couple of drinks a week in the first trimester, up to one a day in the second and third; three to four eight-ounce cups of coffee a day throughout pregnancy—are much less restrictive. Her book, published in 2013, sparked a lot of conversation. It is part of a growing number of evidence-based pregnancy resources that look critically at widely accepted data and advice, and
