OBJECTIVE: We assessed the relationships between active labor and neonatal death, neonatal brain damage, and disabling cerebral palsy in low-birth-weight infants. STUDY DESIGN: A population-based cohort of 961 infants with birth weights of 580 to 2000 g and gestational ages >or=26 completed weeks. Neonatal brain damage was assessed by ultrasound scanning in the first weeks of life; disabling cerebral palsy was assessed at 2 years of age (corrected for gestational age). RESULTS: After being controlled for possible confounders, active labor was associated significantly with an increased risk of parenchymal echodensities/lucencies and/or ventricular enlargement (odds ratio, 2.3; 95% CI, 1.2-4.5) but not with germinal matrix/intraventricular hemorrhage (odds ratio, 1.3; 95% CI, 0.8-2.1), neonatal death (odds ratio, 1.8; 95% CI, 0.8-4.0), or disabling cerebral palsy (odds ratio, 1.6; 95% CI, 0.7-3.7). In vertex presentations only, active labor was associated with a nearly 4-fold increase in risk of neonatal death (odds ratio, 3.8; 95% CI, 1.3-10.9). In nonvertex presentations only, active labor was associated strongly with parenchymal echodensities/lucencies and/or ventricular enlargement (odds ratio, 4.3; 95% CI, 1.2-15.6) and disabling cerebral palsy (odds ratio, 8.2; 95% CI, 1.4-49.9). CONCLUSION: The only adverse outcome that was associated consistently with active labor was parenchymal echodensities/lucencies and/or ventricular enlargement. Fetal presentation modified the relationships between active labor and adverse outcomes. Delivery mode (whether vaginal or cesarean delivery) was not associated with any of the outcomes that were evaluated.
OBJECTIVE: We assessed the relationships between active labor and neonatal death, neonatal brain damage, and disabling cerebral palsy in low-birth-weight infants. STUDY DESIGN: A population-based cohort of 961 infants with birth weights of 580 to 2000 g and gestational ages >or=26 completed weeks. Neonatal brain damage was assessed by ultrasound scanning in the first weeks of life; disabling cerebral palsy was assessed at 2 years of age (corrected for gestational age). RESULTS: After being controlled for possible confounders, active labor was associated significantly with an increased risk of parenchymal echodensities/lucencies and/or ventricular enlargement (odds ratio, 2.3; 95% CI, 1.2-4.5) but not with germinal matrix/intraventricular hemorrhage (odds ratio, 1.3; 95% CI, 0.8-2.1), neonatal death (odds ratio, 1.8; 95% CI, 0.8-4.0), or disabling cerebral palsy (odds ratio, 1.6; 95% CI, 0.7-3.7). In vertex presentations only, active labor was associated with a nearly 4-fold increase in risk of neonatal death (odds ratio, 3.8; 95% CI, 1.3-10.9). In nonvertex presentations only, active labor was associated strongly with parenchymal echodensities/lucencies and/or ventricular enlargement (odds ratio, 4.3; 95% CI, 1.2-15.6) and disabling cerebral palsy (odds ratio, 8.2; 95% CI, 1.4-49.9). CONCLUSION: The only adverse outcome that was associated consistently with active labor was parenchymal echodensities/lucencies and/or ventricular enlargement. Fetal presentation modified the relationships between active labor and adverse outcomes. Delivery mode (whether vaginal or cesarean delivery) was not associated with any of the outcomes that were evaluated.