The objective was to examine the effect of twin-to-twin delivery intervals on neonatal outcome for second twins.
This was a retrospective, hospital-based study, performed at a university teaching hospital in Western Sweden. Twin deliveries between 2008 and 2014 at ≥32 + 0 weeks of gestation, where the first twin was delivered vaginally, were included. Primary outcome was a composite outcome of metabolic acidosis, Apgar < 4 at 5 min or peri/neonatal mortality in the second twin. Secondary outcome was a composite outcome of neonatal morbidity.
A total of 527 twin deliveries were included. The median twin-to-twin delivery interval time was 19 min (range 2–399 min) and 68% of all second twins were delivered within 30 min. Primary outcome occurred in 2.6% of the second twins. Median twin-to-twin delivery interval was 34 min (8–78 min) for the second twin with a primary outcome, and 19 min (2–399 min) for the second twin with no primary outcome ( p = 0.028). Second twins delivered within a twin-to-twin interval of 0–30 min had a higher pH in umbilical artery blood gas than those delivered after 30 min (pH 7.23 and pH 7.20, p < 0.0001). Secondary outcome was not associated with twin-to-twin delivery interval time. The combined vaginal-cesarean delivery rate was 6.6% ( n = 35) and the rate was higher with twin-to-twin delivery interval > 30 min ( p < 0.0001).