OBJECTIVE: To investigate adverse perinatal outcomes and gestational weight gain trajectories in women with lifetime (current/past) eating disorders (ED: anorexia nervosa [AN] and bulimia nervosa [BN]). DESIGN: A longitudinal population-based birth cohort. SETTING: Rotterdam, the Netherlands. SAMPLE: Women who enrolled prenatally, had complete information on exposure (lifetime ED), and gave birth to a live singleton (n = 5256). Four groups of exposed women: lifetime AN (n = 129), lifetime BN (n = 209), lifetime AN + BN (n = 100), other lifetime psychiatric disorder (n = 1002) were compared with unexposed women (n = 3816). METHODS: Perinatal outcomes and gestational weight gain were obtained from obstetric and midwifery records, self-report and objective measurements. Exposed women were compared with unexposed women within the cohort using linear, logistic regression and mixed models. MAIN OUTCOME MEASURES: Any pregnancy, delivery and postnatal complications. Birthweight adjusted for gestational age, prematurity (born <37 weeks), small-for-gestational age; maternal weight gain during pregnancy. RESULTS: Maternal AN was positively associated with suspected fetal distress. No differences were found in mean birthweight, prevalence of a small-for-gestational-age, or premature birth. Relative to unexposed women, women with AN had, on average, a lower body weight but a higher rate of weight gain subsequently; whereas women with BN had a higher body weight but a lower rate of weight gain. CONCLUSIONS: Maternal lifetime ED is associated with few adverse perinatal outcomes in this sample. Differential gestational weight gain patterns in women with AN and BN are consistent with possible biological compensatory mechanisms aimed at protecting the fetus.