Abstract
Background. The aim of this study was to compare the effect of fetal presentation and mode of delivery on infant outcome in a nation-wide study. Methods. In a retrospective observational cohort study, we compared, with the help of Finnish Medical Birth Register and other nation-wide registers, the short-term and long-term outcome of infants born by breech vaginal ( n = 1270) or by vertex vaginal delivery ( n = 128 683) or through planned cesarean section (CS) in breech ( n = 1640) or vertex ( n = 4997); the pregnancies were otherwise entirely normal. Results. One perinatal death occurred in the breech vaginal group and 23 deaths in the vertex vaginal group ( p = 0.112), but none in either CS group. Breech vaginal delivery was associated with increased risk of Apgar scores 6 or less at age 1 min (OR 7.65, CI 6.41-9.12) and at age 5 min (OR 6.42, CI 4.36-9.45) as compared with vertex vaginal delivery. These odd ratios were also elevated (OR 4.59, CI 3.48-7.08 and OR 7.58, CI 3.09-18.66, respectively) when compared with breech planned CS. Yet the risk for birth trauma of infants in the breech vaginal group was smaller (OR 0.70, CI 0.51-0.96) than that in the vertex vaginal group but this risk was smallest in the planned CS groups. A number of other neonatal complications occurred equally commonly in each group. Breech infants born vaginally needed fewer admissions (OR 0.58, 0.47-0.72) to out-patient departments and the cumulative incidence of long-term morbidity in the breech vaginal group was smaller (OR 0.47, CI 0.28-0.80) to the age of 7 years than that in the breech planned CS. The maturity for starting school and school performance during the first two school years showed no dependence on mode of delivery. Conclusion. Apart from Apgar suppression, elective vaginal delivery of a full-term breech fetus in highly selected pregnancies does not cause additional neonatal hazards as compared with full-term vertex deliveries. The immediate outcome was best for breech or vertex infants born through elective CSs.