Prediction Model for Failed Vacuum Assisted Delivery: A Retrospective Cohort Study

Area of Science:

• Obstetrics and Gynecology
• Maternal-Fetal Medicine
• Clinical Prediction Modeling

Background:

• Vacuum-assisted delivery (VAD) is a common obstetric procedure.
• Failed VAD can lead to urgent cesarean delivery (CD) and increased maternal and neonatal morbidity.
• Predictive tools are needed to identify pregnancies at risk for VAD failure.

Purpose of the Study:

• To determine risk factors associated with failed vacuum-assisted delivery (VAD).
• To develop and validate a clinically based predictive model for VAD failure.
• To aid obstetricians in VAD decision-making and patient counseling.

Main Methods:

• Retrospective cohort study (2011-2023) at a tertiary medical center.
• Included singleton pregnancies with a VAD attempt.
• Defined VAD failure by cup detachments, extraction duration, or conversion to urgent CD.

Main Results:

• 1.9% of VAD attempts (172/8885) failed, resulting in urgent CD.
• Identified risk factors: labor induction, deep fetal head station, prolonged second stage, preeclampsia, high birthweight (>3750g), and male fetus.
• Developed prediction score with good discriminatory performance (AUC 0.723), validated internally (AUC 0.764).

Conclusions:

• A validated predictive model for VAD failure was developed.
• The model can assist obstetricians in VAD decision-making and risk stratification.
• Identifies parturients at higher risk for complicated deliveries, enabling proactive management.