Objective: Adrenocortical carcinoma (ACC) is a rare, severe disease. Pregnancy-associated ACC has rarely been reported. We wished to evaluate the characteristics and prognosis of ACC diagnosed in patients during pregnancy or in the postpartum period, comparing them with those for ACC diagnosed in nonpregnant women. Design: Clinical presentation, hormonal secretion, staging, survival, and obstetric data are reported. Patients were included between 1963 and 2007. Mean follow-up was 48 months. Patients and methods: This is a retrospective cohort study carried out at a referral center. All female patients aged 16-49 years diagnosed with ACC during the observation period were included (nZ110). Twelve of these women were pregnant or in the first 6 months after delivery. Hormonal secretion, staging, obstetric data, and survival were analyzed. For the survival analysis, pregnant patients were compared with a subgroup of nonpregnant women matched for age, stage, and year of diagnosis (1 pregnant patient/2 controls). Results: Adrenocortical tumors diagnosed during pregnancy or in the postpartum period tend to be more often cortisol-secreting tumors (PZ0.06) and to be discovered at a more advanced stage than those in nonpregnant women, although the differences were not significant. Fetal outcome was poor. Overall survival of the mother was worse than that of matched controls (hazard ratio of death: 3.98, confidence intervalZ1.34-11.85, PZ0.013). Conclusion: ACC diagnosed during pregnancy or in the postpartum period is associated with a poor fetal outcome and a poorer prognosis than ACC diagnosed in nonpregnant women.