On today’s show, we meet a woman who is trying to bring nuance and subtlety to a world of black-and-white rules: pregnancy. Emily Oster is an economist and the author of a book called Expecting Better. Like our own Chana Joffe-Walt — who takes a break from maternity leave to host today’s show — Oster found herself confused and frustrated by all the rules of pregnancy. Unlike Chana, Emily Oster decided to read almost every study that had every been conducted on pregnancy and risk. Today, we talk to Oster about what she discovered. (Spoiler: A glass of wine is Ok.)