Increased composite maternal and neonatal morbidity associated with ultrasonographically suspected fetal macrosomia

To determine the composite risk of maternal and neonatal morbidity in pregnancies with suspected fetal macrosomia.

In a retrospective study of laboring women delivering singleton, term neonates, we defined 3 groups of patients by estimated fetal weight (EFW) in grams, using ultrasound: (1) <4000, (2) 4000-4499, and (3) 4500+, and tested them for association with a composite outcome using multivariable logistic regression models. The measure of composite morbidity included: shoulder dystocia, third/fourth degree perineal laceration, postpartum hemorrhage, maternal length of stay (LOS) ≥ 5 days, neonatal birth trauma, meconium aspiration syndrome, perinatal infection, and neonatal LOS ≥ 5 days. Because of potential interactions between diabetes and birthweight, women with maternal diabetes were examined separately.

Of 8,843 deliveries, the proportion with composite morbidity by group was: (1): 26.2%, (2): 41.2%, and (3): 63.6% (p < 0.0001). The OR (95% CI) for groups (2) and (3) were: 1.9 (1.2-2.9) and 2.1 (0.6-7.2), for diabetics (9.7% of the final study population), and 2.3 (1.9-2.7) and 3.9 (2.2-6.9), for non-diabetics.

Suspected fetal macrosomia appeared associated with increased risk for a composite measure of childbirth morbidity.