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Recording available 2/16-5/2
Recording available 2/16-5/2
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Abstract Award
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Poster Session 2

Category: Clinical Obstetrics

Poster Session 2

(641) Natural onset of labor in twin pregnancies: a real-world cohort study

Wednesday, February 11, 2026
3:30 PM - 5:00 PM  

    Submitting Author and Presenting Author(s)

  • Roie Alter, MD (he/him/his)

    Hadassah Medical Center and Hebrew University of Jerusalem, Jerusalem, Israel
    Jerusalem, Yerushalayim, Israel

    • Coauthor(s)

  • IA

    Inbal Akavian, MD, MPH

    Hadassah Ein-karem hospital, Obstetrics and gynecology department, Jerusalem
    Jerusalem, Yerushalayim, Israel

  • NL

    Naama Lessans, MD

    Department of Obstetrics and Gynecology, Hadassah Ein Kerem Medical Center, Faculty of Medicine, Hebrew University of Jerusalem
    Jerusalem, Yerushalayim, Israel

  • yE

    yossef Ezra, MD, PhD

    Hadassah Medical Center and Hebrew University of Jerusalem, Jerusalem, Israel
    Hadassah Medical Center and Hebrew University of Jerusalem, Jerusalem, Israel., Yerushalayim, Israel

  • Doron Kabiri, MD, MPH (he/him/his)

    Hadassah Medical Center and Hebrew University of Jerusalem, Jerusalem, Israel
    Hadassah Medical Center and Hebrew University of Jerusalem, Jerusalem, Israel., Yerushalayim, Israel

Objective:
The optimal timing for elective cesarean delivery in twin pregnancies remains controversial, with guidelines varying between 37+0-37+6 weeks and 38+0-38+6 weeks. This study aimed to determine gestational age distribution of spontaneous labor onset in twin pregnancies and evaluate whether findings support scheduling elective cesarean delivery at 37 rather than 38 weeks

Study Design:

This retrospective cohort study included all live twin births ≥23+0 weeks between 1/2019 and 3/2025 at a high-volume tertiary center. Only pregnancies with spontaneous labor onset were included. Cases involving labor induction, prelabor cesarean delivery, or intrauterine fetal demise were excluded. Data were extracted from electronic medical records. The primary outcome was gestational age at spontaneous labor onset.

Results:

Among 1396 twin pregnancies with spontaneous labor onset, the mean gestational age at delivery was 35.9 ± 2.6 (median 36.6) weeks. The majority of spontaneous deliveries occurred before traditional elective timing: 812(58.2%) pregnancies delivered before 37+0 weeks, and 1175(84.2%) pregnancies  delivered before 38+0 weeks. Only 221(15.8%) pregnancies  were delivered at or after 38+0 weeks. Distribution by gestational age categories showed: 201(14.4%) births before 34 weeks, 611(43.8%) births  at 34+0-36+6 weeks, 363(26.0%) births  at 37+0-37+6 weeks, 175(12.5%) births  at 38+0-38+6 weeks, and 46(3.3%) births  at 39+ weeks. The peak incidence of spontaneous labor occurred between 35-37 weeks of gestation.

Conclusion:

The vast majority(84.2%) of twin pregnancies with spontaneous labor onset deliver before 38+0 weeks, providing compelling evidence supporting elective cesarean delivery at 37+0 rather than 38+0 weeks. Scheduling at 37 weeks would prevent emergency interventions in 26.0% of pregnancies while affecting only 41.8% of the cohort. Waiting until 38 weeks would benefit only 15.8% while placing 84.2% at risk for unplanned delivery. This strongly supports earlier delivery timing and may reduce emergency rates and maternal-fetal complications.