Percentage change in body mass index or gestational weight gain: Which is a better predictor of foetal macrosomia?

Abstract

The aim of the study was to evaluate gestational weight gain (GWG) and percentage change in body mass index (BMI) for prediction of foetal macrosomia. A total of 409 term pregnant women, of whom 86 delivered macrosomic infants (> 4000 g) and 323 delivered non-macrosomic infants were recruited for the study. GWG and body mass index at delivery were significantly higher in the macrosomic than non-macrosomic group (15.8 ± 5.6 vs 13.9 ± 5.6, and 31.4 ± 4.3 vs 29.5 ± 4.3, respectively) (p < 0.05). The receiver operating characteristic curve analysis for testing the significance of weight gain in prediction of macrosomia showed an area under curve of 0.58 (p = 0.012, 95% confidence interval [CI] = 0.52-0.65), and significance of percentage change in BMI in prediction of macrosomia revealed an area under curve of 0.52 (p = 0.51, 95% CI = 0.46-0.59). BMI percentage changes both in obese (BMI ≥ 25) and non-obese (BMI < 25) groups were not statistically significant (p > 0.05). BMI percentage change does not seem to be a strong predictor of foetal macrosomia, and GWG was not found to be an independent risk factor after multivariate regression analysis was performed.

Keywords: Body mass index; foetal macrosomia; gestational weight gain.