Head-to-body delivery interval using 'two-step' approach in vaginal deliveries: effect on umbilical artery pH

Study design. aEuro integral Prospective observational study on vaginal deliveries with singleton cephalic fetuses at term from June to December 2005. Clinical variables were evaluated in reference to umbilical artery pH and evidence of neonatal acidemia, defined as pH aEuroS < a parts per thousand currency sign aEuroS7.10 or base excess (BE) aEuroS < a parts per thousand currency sign aEuroS--12 in a multivariate model.Results. aEuro integral Head-to-body interval was timed and recorded in 789 deliveries. The mean head-to-body interval was 88 aEuroS +/-+/- aEuroS61 s. Although head-to-body interval was significantly correlated to umbilical artery pH (p aEuroS== aEuroS0.02), the decline in umbilical artery pH in relation to the head-to-body interval was clinically not significant (0.0078 units for every additional minute of the interval). At the multivariate analysis, umbilical artery pH aEuroS < a parts per thousand currency sign aEuroS7.10 and/or BE aEuroS < a parts per thousand currency sign aEuroS--12 were significantly related to abnormal fetal heart rate tracing during the second stage (p aEuroS== aEuroS0.012) and operative vaginal delivery (p aEuroS== aEuroS0.045), but not to head-to-body interval (p aEuroS== aEuroS0.25). Shoulder dystocia occurred in three cases (0.38%%).Conclusion. aEuro integral A ''two-step'' approach to birth does not significantly increase the risk of neonatal acidemia.