Risk factors for recurrent macrosomia and child outcomes

Women who had delivered a macrosomic newborn will have a higher risk to deliver another macrosomia. We aimed to examine the recurrence risk of macrosomia in the subsequent pregnancy and the implications in long-term child health.

Data from the Collaborative Perinatal Project, a longitudinal birth cohort with 54,371 singleton births, were used. 401 recurrent macrosomic infants (macro-macro) and 1327 normal weight babies with a macrosomia in the last pregnancy (macro-normal) were selected to explore risk factors for recurrent macrosomia. Furthermore, 768 newly onset macrosomia with normal birthweight infant in previous pregnancies (normal-macro) were identified to examine long-term health effects of recurrent macrosomia.

The recurrent rate of macrosomia was 23.2% [95% confidence interval (CI) 21.2%, 25.2%]. White race, higher pre-pregnant body mass index (BMI), more gestational weight gain, male infant and more prior macrosomic infants were significant risk factors for recurrent macrosomia. At 4 years of age, recurrent macrosomic infants had a higher BMI (16.7 vs. 16.1 kg/m², adjusted β: 0.36, 95% CI: 0.12, 0.60) and a higher risk of overweight and obesity (adjusted OR: 1.56, 95% CI: 1.10, 2.23) than infants with normal birthweight after a previous macrosomic sibling. There was no significant difference between recurrent macrosomia and newly onset macrosomia in child outcomes after adjustment for covariates.

Fetal macrosomia has a high recurrence rate in the following pregnancy. Higher maternal pre-pregnant BMI and gestational weight gain are still important risk factors for recurrence of macrosomia, which in turn increases the risk for childhood obesity.