Overview

The term "fetal macrosomia" is used to describe a newborn who's much larger than average.

A baby who is diagnosed as having fetal macrosomia weighs more than 8 pounds, 13 ounces (4,000 grams), regardless of his or her gestational age. About 9% of babies worldwide weigh more than 8 pounds, 13 ounces.

Risks associated with fetal macrosomia increase greatly when birth weight is more than 9 pounds, 15 ounces (4,500 grams).

Fetal macrosomia may complicate vaginal delivery and can put the baby at risk of injury during birth. Fetal macrosomia also puts the baby at increased risk of health problems after birth.