Maternal and Perinatal Outcomes in Pregnancies Complicated by Predominantly Benign Ovarian Lesions: A Retrospective Case-Control Study of 305 Pregnancies

Background: Ovarian lesions during pregnancy pose diagnostic and therapeutic challenges for clinicians. This study aimed to describe the characteristics of ovarian lesions diagnosed during pregnancy and compare maternal and perinatal outcomes with those of pregnancies without ovarian pathology. Methods: A retrospective case–control study was conducted on 305 pregnant women hospitalized at the Department of Obstetrics and Perinatology in Lublin (2011–2020). The study group comprised 105 women with benign ovarian neoplasms (ICD-10 D27; n = 102) or ovarian cancer (C56; n = 3). The reference group comprised 200 women without ovarian pathology, selected by simple random sampling from hospital records. The main outcomes were mode of delivery, duration of pregnancy, birth weight, and APGAR scores. Comorbidities, neonatal diagnoses, and correlations were analyzed as exploratory outcomes using the false discovery rate (FDR) correction. Results: Maternal age did not differ between the groups (p = 0.242), whereas BMI was lower in the study group (26.4 vs. 28.2 kg/m2; p = 0.001), but not among women who delivered in the department (p = 0.777). Caesarean delivery was recorded in 57/58 women who delivered in the department (98.3%) vs. 97/200 (48.5%) in the reference group (p < 0.001). In the worst-case sensitivity analysis (n = 99), the proportion was 57.6% (p = 0.143). The gestational age at delivery was slightly lower in the study group than in the reference group (38.2 vs. 38.8 weeks; p = 0.009). Overall, 42% of the lesions were first detected during the caesarean section. Birth weight (p = 0.696) and APGAR scores (p = 0.418) did not differ. Among newborns with available records (48 vs. 198), atrial septal defects were more frequent in the study group (22.9% vs. 6.1%; RR 3.78, 95% CI 1.78–8.04; FDR-adjusted p = 0.022). Lesion size was weakly correlated with the number of maternal comorbidities (rho = 0.247; p = 0.016). Conclusions: In this cohort of predominantly benign ovarian lesions, birth weights and APGAR scores were comparable to those of the reference group. The high caesarean rate largely reflects intraoperative lesion detection and incomplete data rather than the effect of the lesion itself, and the neonatal findings are hypothesis-generating.