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Recording available 2/16-5/2
Recording available 2/16-5/2
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Poster Session 4

Category: Operative Obstetrics

Poster Session 4

(1068) A Risk Model for Intrapartum Cesarean Delivery in Women with BMI ≤18.5

Thursday, February 12, 2026
3:30 PM - 5:00 PM  

    Submitting Author and Presenting Author(s)

  • Einat n. Tako, MD

    Resident
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
    Tel Aviv, Tel Aviv, Israel

    • Coauthor(s)

  • Itai Atar, MD, MPH

    Resident
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
    Tel Aviv, Tel Aviv, Israel

  • Itamar Gilboa, MD

    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel

  • Daniel Gabbai, MD, MPH

    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel

  • YY

    Yariv Yogev, MD

    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center Gray Faculty of Medicine, Tel Aviv University, Israel
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel

  • Emmanuel Attali, MD (he/him/his)

    Head of Maternal Wards
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center
    Lis Hospital for Women’s Health, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel

Objective:
As scarcity of data exists regarding risk factors for intrapartum cesarean delivery (CD) in underweight women, we aimed to identify these risk factors and develop a risk prediction score in women with BMI ≤18.5.

Study Design:
A retrospective cohort study conducted at a single university-affiliated tertiary center included women with BMI ≤18.5 who planned a trial of labor between 2012 and 2025. Women who opted for elective CD or with nonviable fetuses were excluded. Maternal, obstetric, and neonatal characteristics were compared between women who delivered vaginally and those who underwent intrapartum CD. Risk factors were assessed using univariate and multivariate analyses. Risk prediction score was developed based on a multivariate model. Model performance was evaluated using receiver operating characteristic curve analysis.

Results:

1. During the study period, 147,045 women delivered at our center, of whom 8,956 (6.1%) had BMI ≤18.5 and attempted a trial of labor.

2. Among them, 292 (3.3%) had intrapartum CD with the most common was non reassuring fetal heart rate (50%) followed by arrest of dilatation, descent (12.6%). Other indications included multiple pregnancy-related indications (5.5%), failed induction (3.7%) and failed vacuum extraction (2.7%).

3. Independent risk factors included previous CD (OR 8.61, 95% CI 4.92–15.04), multiple gestation (OR 5.52, 95% CI 3.26–9.34), intrapartum antibiotic use (OR 4.93, 95% CI 3.81–6.39), nulliparity (OR 4.53, 95% CI 3.18–6.47), induction of labor (OR 2.49, 95% CI 1.86–3.32), preeclampsia (OR 2.41, 95% CI 1.15–5.06) and maternal age >40 (OR 2.06, 95% CI 1.28–3.32).

4. Using a cutoff of 7, with sensitivity of 78% and specificity of 77%, a risk score incorporating these factors demonstrated good predictive performance with AUC of 0.83.

Conclusion:
This study provides actionable insights into intrapartum CD risk among underweight women. The proposed prediction model offers a practical tool to support clinical decision-making, optimize labor management and improve maternal and neonatal outcomes for underweight women.