New moms are at risk for developing serious mental illness–not only the postpartum depression commonly understood, thanks to the advocacy of Brooke Shields and her memoir “Down Came the Rain,” but also schizophrenia and bipolar disorder. Last month, Danish researchers published their study in the Journal of the American Medical Association, which was the largest ever to look at postpartum depression, and the first to consider schizophrenia and other kinds of mental illness as different faces of serious postpartum depression.

The Danish study collected civic and health records from over a million first-time parents over a span of three decades, and found that the first three months after women have their first baby is riskiest, especially the first few weeks. During the first 10 to 19 days, new mothers were seven times more likely to be hospitalized with some form of mental illness than women with older infants. Compared to women with no children, new mothers were four times more likely to be hospitalized with mental problems.

New dads aren’t as susceptible (go figure). Researchers suggest that could be because of a woman’s hormones and all the changes taking place after birth, or that a woman carries more of the parenting burden (you think?).

Reporter Lindsey Tanner summarizes the study in her Associated Press article, “Study: Moms at Risk for Mental Problems.”