Short-term maternal and neonatal outcomes by mode of delivery. A case-controlled study

Side-by-side comparisons of short-term maternal and neonatal outcomes for spontaneous vaginal delivery, instrumental vaginal delivery, planned caesarean section and caesarean section during labor in patients matched for clinical condition, age, and week of gestation are lacking. This case-controlled study was undertaken to evaluate short-term maternal and neonatal complications in a healthy population at term by mode of delivery.

Four groups of healthy women, with antenatally normal singleton pregnancies at term, who underwent instrumental vaginal delivery (no. 201), spontaneous delivery (no. 402), planned caesarean section without labor (no. 402) and caesarean section in labor (no. 402) have been retrospectively selected. Outcome measures were maternal and neonatal short-term complications. Odds ratios (OR) and 95% confidence intervals (CI) were calculated.

Maternal complications were mostly associated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 6.9; 95% CI: 2.9-16.4 and OR 3.0; 95% CI 1.1-8.8, respectively, versus spontaneous deliveries). No significant differences in overall complications were observed between spontaneous vaginal deliveries and caesarean sections, whether planned or in labor. By comparison with caesarean sections in labor, instrumental deliveries significantly increased the risk of complications (OR: 3.2; 95% CI: 1.6-6.5). Neonatal complications were also mostly correlated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 3.5; 95% CI: 1.9-6.7 and OR 3.8; 95% CI 2.0-7.4, respectively, versus spontaneous deliveries). By comparison with caesarean sections in labor, instrumental vaginal deliveries significantly increased the risk of complications (OR: 4.2; 95% CI: 2.4-7.4).

In healthy women with antenatally normal singleton pregnancies at term, instrumental deliveries are associated with the highest rate of short-term maternal and neonatal complications.