- Objective The objective was to determine the prevalence of maternal and perinatal complications among patients with rheumatologic diseases (RD) and to investigate the maternal risk factors for preeclampsia and preterm delivery among RD patients. Study design A retrospective population-based cohort study was conducted. The study group comprised women with RD; the control group comprised patients without RD. The obstetric and neonatal outcomes of the groups were compared, and the data were obtained from a computerized database. Results During the study period, there were 179 deliveries by 125 women with RD. The prevalence of severe preeclampsia, chronic hypertension, pregestational diabetes, oligohydramnios, preterm deliveries and cesarean sections was significantly higher in the RD group than in the control group. Mean birth weight was significantly lower in the study group compared with the general population. Maternal RD was found to be an independent risk factor for preterm delivery and severe preeclampsia (OR 3.59; 95% CI: 2.52–5.11; OR 3.05; 95% CI: 1.44–6.45, respectively). The presence of chronic hypertension in patients with RD was found to be an independent risk factor for severe preeclampsia and preterm delivery (OR 12.2; 95% CI: 2.1–69.8; OR 3.8; 95% CI: 1.1–12.7, respectively). Conclusion Chronic hypertension is an independent risk factor for preterm delivery and severe preeclampsia among RD patients.