Birth outcomes following pelvic ring injury: A retrospective study

Objective: To report obstetric outcomes in pregnant women with previous pelvic ring injury (PRI) and investigate the correlation between residual pelvic deformity and the mode of delivery.Design: Retrospective cohort study.Setting: Single medical centre in Taiwan.Population: Forty-one women with PRI histories from 2000 to 2021 who subsequently underwent pregnancy and delivery.Methods: All patients had complete PRI treatment and radiological follow up for at least 1 year. The demographic data, radiological outcomes after PRI and obstetric outcomes were collected to investigate the potential factors of delivery modes using non-parametric approaches and logistic regression. Caesarean section (CS) rates among different subgroups were reported.Main outcome measures: Comparisons of demographic data and radiological outcomes (Matta/Tornetta criteria and Lefaivre criteria) after PRI among patients who had subsequent pregnancy and underwent vaginal deliveries (VD) or CS.Results: There were 14 VD and 27 CS in 41 patients. Nine patients underwent CS because of their PRI history, 12 patients underwent CS for other obstetric indications and 20 underwent trial of labour. Based on the logistic regression model, retained trans-iliosacral implants did not significantly increase the risk of CS (odds ratio [OR] 1.20; 95% CI 0.17-8.38). Higher pelvic asymmetry value by Lefaivre criteria was a potential risk factor for CS after previous PRI (OR 1.52; 95% CI 1.043-2.213).Conclusions: VD is possible after PRI. Retained trans-iliosacral implants do not affect the delivery outcome. Residual pelvic asymmetry after PRI by Lefaivre criteria is a potential risk factor for CS.