In plain words
Macrosomia means a baby who is very large at birth. The usual cutoff is 4,000 grams, which is about 8 pounds 13 ounces, or more. It is counted by birth weight, not by how far along the pregnancy is. Large babies are more common when a parent has diabetes, when weight gain in pregnancy is high, or after a previous large baby. Most large babies are born healthy. A large baby can make vaginal birth harder, especially when the shoulders are large, a problem called . Care teams watch for this and plan for it. Ultrasound estimates of size are not very precise, so a provider uses them together with other information. Ask your provider how your baby's size is being measured and what the team would do with the result.
The deeper version
ACOG Practice Bulletin 216 (2020) defines macrosomia as birth weight of 4,000 grams or more, regardless of gestational age. It is associated with maternal diabetes, maternal obesity, excessive , prior macrosomia, and male sex. Ultrasound estimated fetal weight is imprecise, and the bulletin emphasizes discussing the limits of estimation before acting on it. Macrosomia increases the risk of shoulder dystocia, brachial plexus injury, and perineal trauma, and it raises the likelihood of delivery when the estimated weight is high. The controversy concerns the threshold for planned cesarean at high estimated weight, and whether prophylactic reduces harm or adds risk.
Where it comes up
- Gestational diabetesPregnancy: Your Body
- Weight gain in pregnancyPregnancy: Your Body
- Going past your due datePregnancy: Your Body
- Eating with gestational diabetesPregnancy: Eating
What mothers here say about macrosomia
No one has posted under this term yet.
Sources
- American College of Obstetricians and Gynecologists — Practice Bulletin No. 216: Macrosomia, 2020