Impact of Fetal Birth Weight on the Success of Trial of Labor after Previous Cesarean Section: A Cross-Sectional Study

Abstract

Background: Vaginal birth after cesarean section (VBAC) is an established and safe alternative to elective repeat cesarean section (ERCS) in appropriately selected women with a previous lower segment cesarean section. Several maternal and fetal factors influence the success of trial of labor after cesarean (TOLAC), among which fetal birth weight plays a significant role.

Objective: To evaluate the association between fetal birth weight and the success of TOLAC in women with one previous cesarean section.

Material and Methods: This descriptive cross-sectional study was conducted in the Labour room, Department of Obstetrics and Gynecology, Nishtar Medical University / Hospital Multan, from January 2023 to August 2023. A total of 144 women with one previous lower segment cesarean section, singleton cephalic presentation, term pregnancy, and spontaneous labor were included. Patients were categorized according to neonatal birth weight. The outcome variable was successful VBAC. Data were analyzed using SPSS version 26. Chi-square test was applied, and p ≤ 0.05 was considered significant.

Results: Mean maternal age was 29.92 ± 5.08 years and mean gestational age was 37.50 ± 1.65 weeks. Mean fetal birth weight was 3.24 ± 0.48 kg. Successful VBAC occurred in 42.4% (n=61), while 57.6% (n=83) underwent repeat cesarean section. A statistically significant association was observed between fetal birth weight and VBAC success (χ²=6.32, p=0.043). Stratification showed significant associations with parity, gestational age, and previous birth weight.

Conclusion: Fetal birth weight is significantly associated with VBAC success. Proper estimation of fetal weight may improve patient selection and reduce unnecessary repeat cesarean sections.

Keywords: VBAC, TOLAC, Cesarean Section, Fetal Birth Weight, Vaginal Birth After Cesarean, Maternal Outcomes.