ELEVATED MATERNAL BMI AMONG WOMEN WITH SUCCESSFUL VAGINAL BIRTH AFTER CESAREAN: EXPERIENCE FROM A 9-YEAR SINGLE-CENTER SERIES

Sergei Slavov; Svetlozar Slavov

doi:10.35120/medisij0503109s

Authors

Sergei Slavov University Hospital of Obstetrics and Gynecology “Maichin Dom”, Sofia, Bulgaria Department of Obstetrics and Gynecology, Medical University, Sofia, Bulgaria Author
Svetlozar Slavov University Hospital of Obstetrics and Gynecology “Maichin Dom”, Sofia, Bulgaria Department of Obstetrics and Gynecology, Medical University, Sofia, Bulgaria Author

DOI:

https://doi.org/10.35120/medisij0503109s

Keywords:

TOLAC, VBAC, body mass index, obesity, overweight, cesarean delivery

Abstract

Maternal obesity is commonly associated with a reduced probability of vaginal birth after cesarean (VBAC), yet body mass index (BMI) alone does not determine the outcome of a trial of labor after cesarean (TOLAC). This study describes the BMI profile of women who achieved VBAC in a tertiary referral center, with particular attention to the representation of overweight and obesity among successful cases.

Objective: To describe the distribution of maternal BMI among successful VBAC cases and to assess the representation of elevated BMI, including severe obesity, within this group.

Materials and methods: A retrospective descriptive case series included 149 successful VBAC deliveries recorded between 2016 and 2025 at the University Hospital “Maichin Dom”, Sofia. BMI was documented in 118 women. Patients were grouped as BMI <25 kg/m², 25.0–29.9 kg/m² and ≥30 kg/m². Obesity was additionally stratified into classes I, II and III. The study describes the characteristics of women who achieved VBAC and does not compare them with women who had a failed TOLAC.

Results: Mean BMI was 28.3 ± 6.6 kg/m² (range 19.0–64.0). Normal BMI was present in 43/118 women (36.4%), overweight in 37/118 (31.4%) and obesity in 38/118 (32.2%). Consequently, 75/118 successful VBAC cases (63.6%) occurred in women with BMI ≥25 kg/m². Among women with obesity, 26 (68.4%) had class I, 7 (18.4%) class II and 5 (13.2%) class III obesity.

Conclusion: Elevated BMI was common rather than exceptional among women who achieved VBAC in this series. Successful vaginal birth was observed across a wide BMI range, including BMI ≥40 kg/m². These findings should not be interpreted as BMI-specific TOLAC success rates, but they illustrate why BMI is better used as one component of individualized counseling than as a stand-alone exclusion criterion.

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