[Macrosomia, shoulder dystocia and elongation of the brachial plexus: what is the role of caesarean section?].

The delivery of a macrosomic infant is associated with a higher risk for maternofoetal complications. Shoulder dystocia is the most feared fetal complication, leading sometimes to a disproportionate use of caesarean section. This study aims to evaluate the interest of preventive caesarean section. We conducted a retrospective study of 400 macrosomic births between February 2010 and December 2012. We also identified cases of infants with shoulder dystocia occurred in 2012 as well as their respective birthweight. Macrosomic infants weighed between 4000g and 4500g in 86.25% of cases and between 4500 and 5000 in 12.25% of cases. Vaginal delivery was performed in 68% of cases. Out of 400 macrosomic births, 9 cases with shoulder dystocia were recorded (2.25%). All of these cases occurred during vaginal delivery. The risk for shoulder dystocia invaginal delivery has increased significantly with the increase in birth weight (p <10-4). The risk for elongation of the brachial plexus was 11 per thousand vaginal deliveries of macrosomic infants. This risk was not correlated with birthweight (p = 0.38). The risk for post-traumatic sequelae was 0.71%. Shoulder dystocia affectd macrosoic infants in 58% of cases. Shoulder dystocia is not a complication exclusively associated with macrosomia. Screening for risky deliveries and increasing training of obstetricians on maneuvers in shoulder dystocia seem to be the best way to avoid complications.