New book claims sushi, wine okay for pregnant women

(CBSNews) - Emily Oster isn't a baby doctor. She's an economist and a mom who wanted to know more about all those rules handed down to women after the pregnancy stick goes pink.

Only two cups of coffee a day! No alcohol. Beware deli meats.

Being pregnant, she said, felt a lot like being a child, so she decided to take a deep dive into research covering everything from wine and weight gain to prenatal testing and epidurals. What she found was some of the mainstays of pregnancy advice are based on inconclusive or downright faulty science.

To this data-cruncher, an associate professor in the University of Chicago's business school, those magical nine months became a question of correlation and causation.

Some of her conclusions? Weight gain during pregnancy is less important than a woman's starting weight and not gaining enough may be more harmful. Light drinking is fine (up to two glasses of wine a week in the first trimester and up to a glass a day in the second and third trimesters). And much of the evidence supports having three to four cups of coffee daily, which made Oster very, very happy.