OBJECTIVE: We aimed to identify factors associated with postpartum psychiatric admission in schizophrenia.METHOD: In a population-based cohort study of 1433 mothers with schizophrenia in Ontario, Canada (2003-2011), we compared women with and without psychiatric admission in the 1st year postpartum on demographic, maternal medical/obstetrical, infant and psychiatric factors and identified factors independently associated with admission.RESULTS: Admitted women (n = 275, 19%) were less likely to be adolescents, more likely to be low income and less likely to have received prenatal ultrasound before 20 weeks gestation compared to non-admitted women. They also had higher rates of predelivery psychiatric comorbidity and mental health service use. Factors independently associated with postpartum admission were age (<20 vs. ≥35 years: adjusted risk ratio, aRR, 0.48, 95% CI 0.24-0.96), income (lowest vs. highest income: aRR 1.67, 1.13-2.47) and the following mental health service use factors in pregnancy: admission (≥35 days/year vs. no days, aRR 4.54, 3.65-5.65), outpatient mental health care (no visits vs. ≥2 visits aRR 0.35, 0.27-0.47) and presence of a consistent mental health care provider during pregnancy (aRR 0.69, 0.54-0.89).CONCLUSION: Certain subgroups of women with schizophrenia may benefit from targeted intervention to mitigate risk for postpartum admission.