How Eating Disorders Affect Fertility and Pregnancy

Eating disorders often disrupt menstrual cycles, but little is known about the long-term effects of eating disorders on fertility and attitudes toward pregnancy. A recent study compared rates of fertility and attitudes toward pregnancy among women with a lifetime history of anorexia nervosa (AN) and bulimia nervosa (BN) and a general population of women.

The study included 11,088 women participating in the Avon Longitudinal Study of Parents and Children (ALSPAC) (BJOG 2011; August 3 [e-pub ahead of print]). All participants were asked to complete questionnaires at 12 and 18 weeks gestation. Among all women, 171 (1.5%) had a lifetime diagnosis of AN; 199 (1.8%) had lifetime diagnoses of BN, and an additional 82 participants (0.7%) had lifetime histories of both AN and BN. The remaining 10,636 women (96%) formed the general population comparison group.

Pregnancy was more likely to be unintentional

A higher proportion of women (39.5%) with a history of AN or BN took longer than 6 months to conceive compared to women in the general population (25%). The results of the study also showed that women with AN and BN were more than twice as likely (6.2%) than the general population group (2.7%) to report that their current pregnancy was unintentional. However, when asked at 18 weeks gestation, only the women with AN but not BN were more likely to report that their current pregnancy was unintentional. In this group of women, 41.5% reported that their pregnancy was unplanned, compared to 28.6% of the women in the general population.

Twenty-one percent of women with AN and 20% of those with AN plus BN, but only 12% of those in the general population—had been seen by a physician for lifetime fertility problems. Women with a history of AN and BN were more likely than those in the general population (6.2% vs. 2.7%, respectively) to have received medical assistance in conceiving their current pregnancies and were more likely to take more than 6 months to conceive. However, the women with eating disorders were no more likely to take longer than 12 months to conceive than were the women in the general population.

A negative reaction at first

Women with eating disorders were more likely to have negative reactions when they first discovered they were pregnant, although these feelings tended to disappear by 18 weeks gestation. Women with histories of lifetime AN or AN plus BN were more likely than women in the general population to view motherhood as a personal sacrifice.

Thus, fertility is only modestly affected among women with lifetime eating disorders. Healthcare providers should counsel women with histories of eating disorders that they probably can have children, even when their menstrual patterns have been disturbed. And, because of the sometimes negative attitudes toward pregnancy, women with eating disorders might require additional psychological support, particularly during the early stages of pregnancy.