Pre-pregnancy body mass index (BMI) and cerclage success

Abstract

Objective: This study was performed to evaluate the effect of pre-pregnancy body mass index (BMI) on the success of cerclage.

Materials and methods: A retrospective cohort study of women who had a history-indicated (HIC) or ultrasound-indicated cerclage (UIC) placed between 1994 and 2011. Based on pre-pregnancy BMI (World Health Organization criteria), three cohorts were defined: normal/overweight (BMI: 20.0–29.9 kg/m²), obese class I/II (BMI: 30.0–39.9 kg/m²) and obese class III (BMI ≥ 40.0 kg/m²). The primary outcome was spontaneous preterm birth (sPTB) <35 weeks. The secondary outcomes included but were not limited to gestational age of delivery, sPTB <37, <32 and <28 weeks, preterm premature rupture of membranes and birth weight.

Results: 375 women were included for analysis. Demographics were similar in the three BMI categories, except black race (p = 0.01). The rates of sPTB <35 weeks were similar between each cohort: 24.3%, 23.0% and 27.7%, respectively (p = 0.81). BMI was not a predictor of any of the secondary outcomes. A HIC was placed in 47.2% and an UIC was placed in 52.8% women. Both unadjusted and adjusted analysis showed no significant difference in sPTB <35 weeks between BMI categories overall or by cerclage type (HIC or UIC).

Conclusions: Pre-pregnancy BMI is not a significant predictor of sPTB <35 weeks in women with HIC or UIC.

• Body mass index
• cervical cerclage
• history-indicated cerclage
• preterm birth
• ultrasound-indicated cerclage

Acknowledgments

We would like to acknowledge Jocelyn A. Sendecki, PhD, and Benjamin Leiby, PhD, for their assistance with statistical analysis.

Declaration of interest

The authors have no potential conflicts of interest to disclose.

This work was presented, in part, as a poster (abstract 493) at the Society of Gynecologic Investigation 57th annual meeting, Orlando, FL, 24–27 March 2010.