The incidence of and risk factors for shoulder dystocia in a tertiary Greek maternity hospital: a retrospective case-control study

Aim: We aimed to determine the incidence of and risk factors for shoulder dystocia in Greek tertiary maternity settings. Design: A retrospective case-control study. Methods: Study of women who gave birth at the University Hospital of Larissa in Greece between 2019 and 2024. We matched every case of women with shoulder dystocia with ten women giving birth without shoulder dystocia. We compared the maternal demographics and the perinatal outcome between cases and controls. Results: A total of 1,536 vaginal births were identified over the study period. There were 21 documented cases of shoulder dystocia (1.4% incidence rate) matched with 210 uncomplicated vaginal births. The median age of women with shoulder dystocia was 28 years (IQR = 25–31), 42.9% were nulliparous, and the median gestational age was 39+2 weeks. There was no postpartum hemorrhage, and perineal trauma was comparable between women with and without shoulder dystocia. No neonates with shoulder dystocia were admitted to the neonatal unit and there were no stillbirths. More than 70% of cases with shoulder dystocia occurred during the afternoon and evening hours. The percentage of male neonates was significantly higher in cases with shoulder dystocia (76.2% vs. 51%; p = 0.02). The only independent predictor for shoulder dystocia was birthweight (OR = 1.24; 95% CI, 1.09–1.40). Conclusion: The incidence of shoulder dystocia and perinatal outcomes are in line with the literature. These local data reflect an efficient maternity service provision and can be used as a benchmark for future comparisons and evaluation, since there is no other similar study within Greek clinical settings that reports on shoulder dystocia.