Eating disorders are prevalent among women of reproductive age, but the effects of bad eating habits on pregnancy and neonatal outcomes have not been well studied. The objective of this study is to assess the risk of adverse pregnancy and neonatal outcomes among women with eating disorders.

This is a population-based cohort study that included all singleton births between January 1, 2003, and December 31, 2004, as recorded by the Swedish Medical Birth Register. Of the participants, a total of 7,542 women with eating disorders were compared with 1,225,321 women without eating disorders. The primary endpoints of the study were adverse pregnancy outcomes (hyperemesis, pre-eclampsia, and anemia) and neonatal outcomes (preterm birth, small or large sizes).

Of 7,542 women, 2,769 women had anorexia nervosa, 1,378 women had bulimia nervosa, and 3,395 women had an unspecified eating disorder. When compared with women without eating disorders, all types of maternal eating disorders were associated with a twofold risk of hyperemesis. Women with active anorexia nervosa were at a higher risk of anemia (RR 2.1) and antepartum hemorrhage (1.6). Women with eating disorders of all subtypes were also at a higher risk of preterm birth and microcephaly.

The findings suggested that maternal eating disorders of all types were associated with an increased risk of adverse pregnancy and neonatal outcomes.