Objective: To determine whether delivery by caesarean is associated with a better neuro-developmental outcome at two years for preterm infants born weighing 1,250 g or less.
Setting: District General Hospital, United Kingdom.
Design: All inborn infants weighing <1,250 g born at St Helier University Hospital between January 1995 and December 2003 were identified from contemporaneously collected computer database. All hospital records were retrieved. Details of the mother, delivery route, Apgar score, details of resuscitation and details of the baby, neonatal progress and neuro-developmental status at two years was transcribed on a pre-designed proforma. Neuro-developmental status assessment at two years of age was carried out by an independent neurodevelopmental paediatrician. Neuro-developmental status was classified as normal, severe, moderate or mild disability.
Statistical analysis: Analysis was done by creating a simple two by two table. Statistical significance was set at p = 0.05. Multivariate and univariate analysis was carried out for a number of confounding variables.
Sample: Total of 411 babies were identified from the data-base. Of these 59 were still born and fourteen though born alive died in the delivery suit. 125 (37%) were excluded from analysis as they were returned to their referring hospitals prior to discharge from hospital. Information about their two-year follow-up was either incomplete or not robust enough to be included in the analysis. Analysis was carried out on 213(63%) for whom we had complete data set at two years of age (103 infants born via vaginal delivery and 110 infants were born by caesarean section).
Outcome measure: Primary outcome measure was to compare survival at discharge and neurodevelopmental status at two years of age of this cohort. Secondary outcome included determining the incidence of grade III or IV intraventricular haemorrhage (IVH), chronic lung disease and necrotising enterocolitis (NEC).
Results: The overall caesarean delivery rate for this cohort was 51.6% while the overall caesarean rate for all births at our hospital during the study period varied between 20 and 23%. Neonatal mortality for those delivered by caesarean was 12.7% compared to 14.5% for those delivered vaginally (p = ns). Overall incidence of any neuro-disability at two years of age was 46.8% for those delivered by caesarean compared to 47.7% for those delivered vaginally (p = ns). There was no difference in those with severe (23.5% vs. 25.0%), moderate (10.4% vs. 9%) or mild (12.5% vs. 13.6%) neuro-disability between the groups nor was there any difference in the number of babies with IVH, chronic lung disease and NEC. Neuro-disability was equally greater in both groups for babies born weighing 750 grams or less and/or born at 26 weeks or less gestation.
Conclusion: Despite the increasing tendency to deliver extremely preterm babies by caesarean, we did not find that it was associated with either reduced mortality or neuro-disability at two years of age. Therefore the method of delivery of very-low-birth weight premature infants should be based on obstetric or maternal indications rather than the perceived outcome of the baby.