Chauhan et al developed an algorithm for delivering a fetus with suspected macrosomia. The authors are from Spartanburg Regional Medical Center (South Carolina), Northwestern University, the University of Maryland and the Medical University of South Carolina.

Macrosomia was defined as a fetal weight >= 4,000 grams.


Most women with a macrosomic fetus can deliver vaginally.


An elective cesarean section should be considered an option if:

(1) The estimated fetal weight was >= 5,000 grams and the pregnancy is uncomplicated (controversial).

(2) The mother has a history of previous cesarean section, no history of prior vaginal delivery, and the estimated fetal weight is >= 4,000 grams.

(3) The mother has diabetes mellitus and the estimated fetal weight is >= 4,500 grams.

(4) The mother has delivered a previous infant with shoulder dystocia.



• For the mother with a history of previous cesarean section, the history of a previous vaginal delivery is significant. If there is no history of a vaginal delivery, then a successful vaginal delivery occurred < 50% of the time and the risk of uterine rupture was almost 4%. If there is a history of previous vaginal delivery then vaginal delivery can be achieved in most (87%) and the risk of uterine rupture is much lower.

• The only complication mentioned is diabetes mellitus. Handling other complications is not discussed, and some may justify cesarean section.

• There is no weight cutoff for a woman with a history of shoulder dystocia in a previous pregnancy.

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