Risk of postnatal depression, miscarriage, and preterm birth in bulimia nervosa: retrospective controlled study.

OBJECTIVE: Bulimia nervosa is common and treatable. An association between bulimia and obstetric complications has been suggested, but sample size and absence of control have limited previous studies. Our aim was to determine if active bulimia nervosa affects obstetric outcome.
METHODS: This was a retrospective case-control comparison of obstetric complications in primigravidae previously treated for bulimia in a specialist eating disorder service. A cohort of 122 women with active bulimia during pregnancy was contrasted against 82 with quiescent bulimia, using structured interviews comprising the Eating Disorders Examination, Structured Clinical Interview for DSM-III-R, and systematic questions addressing obstetric complications.
RESULTS: Odds ratios (ORs) for postnatal depression, miscarriage, and preterm delivery were 2.8 (95% confidence interval [CI], 1.2-6.2), 2.6 (95% CI, 1.2-5.6) and 3.3 (95% CI, 1.3-8.8) respectively. Risk of unplanned pregnancy was markedly elevated (OR, 30.0; 95% CI, 12.8-68.7). Risk estimates were not explained by differences in adiposity, demographics, alcohol/substance/laxative misuse, smoking, or year of birth, but relative contributions of bulimic behaviors were not discerned.
CONCLUSIONS: Active bulimia during pregnancy is associated with postnatal depression, miscarriage, and preterm delivery. Bulimia may be a treatable cause of adverse obstetric outcome.