Poster Session 3
Category: Labor
Poster Session 3
Avihu Krieger, N/A (he/him/his)
The Department of Obstetrics and Gynecology, The Chaim Sheba Medical Center, Ramat-Gan, Israel
Ramat Gan, Tel Aviv, Israel
Michal Axelrod, MD, MPH (she/her/hers)
Sheba Medical Center
Sheba Medical Center, HaMerkaz, Israel
Shiran Bookstein Peretz, MD
Resident
Sheba Medical Center, Ramat Gan, Israel
Ramat Gan, HaMerkaz, Israel
Baha M. Sibai, MD
Professor
Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School at UTHealth Houston
Houston, Texas, United States
Shalom Mazaki-Tovi, MD
The Department of Obstetrics and Gynecology, The Chaim Sheba Medical Center, Ramat-Gan, Israel
Ramat Gan, HaMerkaz, Israel
Michal Fishel Bartal, MD
Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, McGovern Medical School at UTHealth Houston
Houston, Texas, United States
To identify predictors of successful induction of labor (IOL), defined as vaginal delivery, and evaluate unplanned cesarean delivery (CD) risk among nulliparous individuals with singleton pregnancies and hypertensive disorders of pregnancy (HDP) undergoing IOL at term (≥37 weeks).
Study Design:
This retrospective cohort study included all nulliparous individuals with HDP who underwent IOL at term from 2010-2025. We excluded those with multiple gestations or planned CD. We evaluated risk factors for unplanned CD, and maternal and neonatal outcomes according to mode of delivery.
Risk stratification for unplanned CD was then performed using logistic regression by evaluating the cumulative impact of identified predictors including maternal age, Body mass index, severe HDP, thrombocytopenia and the need for cervical ripening.
Results:
Of 6,670 individuals with HDP during the study period, 2,609 (38.6%) underwent IOL at term, and 1,326 (50.8%) nulliparous individuals met inclusion criteria. Of these, 979 (73.8%) had a vaginal delivery, while 347 (26.2%) underwent unplanned CD.
Compared to those who delivered vaginally, individuals undergoing CD were older (32.1 vs 29.8 years, p< 0.001), had a higher body mass index (31.6 vs 29.4 kg/m2, p< 0.001), more frequent thrombocytopenia (3.5% vs 1.5%, p=0.03), higher incidence of severe HDP (16.7% vs 10.7%, p< 0.001) and were more likely to require cervical ripening (70.9% vs 59.5%, p< 0.001) (Table 1). Presence of ≥4 risk factors was associated with a 64.7% CD rate and yielded a positive likelihood ratio (LR) of 5.17 (95% CI 1.92-13.99). CD risk, stratified by cumulative number of identified risk factors, along with corresponding LR, is presented in Figure 2.
Conclusion:
Approximately one in four nulliparous individuals with HDP undergoing IOL at term will end with an unplanned CD. Among those with four identified risk factors the risk rose to nearly two out of three. These findings offer a practical framework for individualized risk estimation and may support shared decision-making regarding mode of delivery in this high-risk population.