Health I.Q.: The Truth About Your Immune System During Pregnancy

Q: We hear it often: The immune system is compromised significantly during pregnancy. But is it true?

A: According to Dr. Sarah Kilpatrick, chair of the Department of Obstetrics and Gynecology at Cedars-Sinai Medical Center in Los Angeles, no. “This is a very simplistic concept and not true,” she explains. “There are many immunologic changes in pregnancy that allow the pregnant woman’s body not to reject the fetus. It is actually much more complex than imagined, but the pregnant woman herself is not immunocompromised.” So what exactly goes on in there? “She does produce high levels of corticosteroids, which are actually anti-inflammatory and may be why some women with autoimmune diseases do better in pregnancy,” she continues. “Pregnant women do seem to get sicker with some respiratory diseases like flu, but that might be because they are diagnosed later, that they don’t get the right treatment or that their lung function changes in pregnancy. And many diseases like HIV or cancer are not worse in pregnant women versus nonpregnant women. So this concept of [a compromised immune system] in pregnancy is really not right.”