Factors associated with fetal macrosomia

OBJECTIVE: To evaluate the clinical factors, as well as weight gain, in a group of pregnant women, associating them with fetal macrosomia in a public institution in Antioquia, Colombia, from 2010-2017. METHODS: A case-control study, using secondary information registries. Cases were defined using newborn weight of ≥ 4000g, while controls were defined as newborn weight between 3000–3999g. A proportion ratio (PR) was established to evaluate factors associated with macrosomia, and a generalized linear model (GLM) of Poisson regression with robust variance was used to evaluate the aspects that best explained macrosomia in the neonate. RESULTS: 122 pregnant women participated in the study, of which 611 were cases and 61 were controls. Of the participants, 44.3% had pre-pregnancy overweight and 48.4% had excess gestational weight gain. Statistically significant differences were found between the groups in the following variables: pre-pregnancy BMI (p = 0.004), gestational weight gain (p = 0.000), gestational diabetes (p = 0.000), and type of delivery (p = 0.004). According to the regression model, a macrosomic newborn is 3.5 times more likely in women with excessive gestational weight gain (95%CI 1.78-7.18) and twice more likely in women who have gestational diabetes (95%CI 1.51-2.76). Of women with pre-pregnancy excess weight, 63% had excess gestational weight gain. CONCLUSIONS: Within this cohort, pre-pregnancy BMI, excess weight gain in pregnancy, and the presence of gestational diabetes were associated with an increased risk of neonatal macrosomia. pre-pregnancy BMI and weight gain in pregnancy are modifiable risk factors that are responsive to nutrition interventions, which can minimize adverse perinatal outcomes.