INCIDENCE OF PERSISTENT BIRTH INJURY IN MACROSOMIC INFANTS - ASSOCIATION WITH MODE OF DELIVERY

OBJECTIVE: Our purpose was to determine the incidence of birth injury in a cohort of macrosomic infants (birth weight >4000 gm) and analyze the association between persistent injury and delivery method. STUDY D ESIGN: Deliveries of 2924 macrosomic infants were reviewed. Outcomes w ere compared with those of 16,711 infants with birth weights between 3 000 and 3999 gm. RESULTS: Macrosomic infants had a sixfold increase in significant injury relative to controls (relative risk 6.7,95% confid ence interval 6.5 to 6.9). Risk of trauma correlated with delivery mod e: forceps were associated with a fourfold risk of clinically persiste nt findings compared with spontaneous vaginal delivery or cesarean sec tion. However, the overall incidence of persistent cases remained low (0.3%); a policy of elective cesarean section for macrosomia would nec essitate 148 to 258 cesarean sections to prevent a single persistent i njury. Avoidance of operative vaginal delivery would require 50 to 99 cesarean sections per injury prevented. CONCLUSIONS: These findings su pport a trial of labor and judicious operative vaginal delivery for ma crosomic infants.