Fetal macrosomia refers to a fetus that is significantly larger than average, generally defined as an estimated fetal weight above 4,000 or 4,500 grams, depending on the clinical context. Risk factors include maternal diabetes, excessive maternal weight gain, post-term pregnancy, and a history of previous macrosomic infants. On ultrasound, macrosomia is suspected when biometric measurements, particularly the abdominal circumference, exceed the 90th percentile, and the estimated fetal weight is above the normal range. Accurate prediction of macrosomia is important because it affects delivery planning, as very large babies have increased risks of shoulder dystocia, birth injuries, and cesarean delivery.
Sonography Term