Neonatal hypoxia of the second twin after vaginal delivery of the first twin: what matters?*

AbstractObjective: Optimal management of twin deliveries is controversial. We aimed to assess potential risk factors correlated to the development of hypoxia in the second twin after vaginal delivery of the first twin.Study design: This is a retrospective observational study including diamniotic twin pregnancies delivering at our Institution at 35 weeks of gestational age or more, weighing ≥1800 g. Hypoxia was defined as at least one of the following: Apgar score 10 minutes, neonatal acidosis (pH ≤7 and/or BE ≥12 mmol/L).Results: A number of 275 diamniotic twin pregnancies met the inclusion criteria and were divided within the following groups: (1) second twin not developing neonatal hypoxia (n = 265); and (2) second twin developing neonatal hypoxia (n = 10). The rate of second twins with neonatal hypoxia during the study period was 3.6% (10/275). Abnormal cardiotocography during the intertwin delivery interval, defined as ACOG category III, was significantly c...