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Laparoscopic Extracorporeal Knot-Tying for Uterine Vessel Occlusion during Hysterectomy with Cervical Cerclage in Large Uteri
Published on: September 12, 2025
Risk factors for classical hysterotomy by gestational age
Sarah S Osmundson1, Matthew J Garabedian, Deirdre J Lyell
1Department of Obstetrics and Gynecology, Lucille Packard Children's Hospital, Stanford University School of Medicine, Stanford, and the Department of Obstetrics and Gynecology, Santa Clara Valley Medical Center, San Jose, California.
Obstetrics and Gynecology
|October 3, 2013
Summary
Classical hysterotomy is common in preterm cesarean deliveries, especially before 26 weeks gestation. Fetal factors like small for gestational age (SGA) status and noncephalic presentation increase its likelihood.
Area of Science:
- Obstetrics and Gynecology
- Maternal-Fetal Medicine
- Surgical Innovation
Background:
- Classical hysterotomy, a vertical uterine incision, carries higher risks than low transverse incisions.
- Understanding the incidence and predictors of classical hysterotomy is crucial for optimizing cesarean delivery practices, particularly in preterm gestations.
Purpose of the Study:
- To determine the incidence of classical hysterotomy across various preterm gestational ages.
- To identify maternal and fetal factors associated with an increased likelihood of classical hysterotomy during cesarean delivery.
Main Methods:
- Secondary analysis of a prospective observational cohort from the Maternal-Fetal Medicine Network.
- Inclusion of women with singleton gestations undergoing cesarean delivery with a known hysterotomy.
- Multivariable regression analysis to assess factors influencing hysterotomy type, including gestational age, maternal characteristics, fetal presentation, and delivery circumstances.
Main Results:
- Out of ~36,000 women, 4.3% underwent classical hysterotomy, with incidence peaking at 53.2% between 24-25 weeks gestation.
- Classical hysterotomy likelihood increased with small for gestational age (SGA) status (OR 2.71), birth weight ≤1,000 g (OR 1.51), and noncephalic presentation (OR 2.03).
- Factors influencing likelihood included gestational age, labor status, multiparity, and prior cesarean delivery; emergent delivery was not a predictor.
Conclusions:
- Approximately 50% of cesarean deliveries between 23-26 weeks gestation involve a classical hysterotomy, with risk decreasing thereafter.
- Fetal factors, particularly SGA and noncephalic presentation, are significant predictors of classical hysterotomy.
- These findings highlight the importance of considering fetal characteristics when planning cesarean deliveries in preterm gestations.
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