Abstract Objectives: To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin. Additionally, to investigate predictors of adverse outcome in both twins. Methods: Data included vaginally delivered twins (≥ 36 weeks) from Copenhagen University Hospitals (2001-09). The association between delivery interval and adverse outcome parameters were compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression. Results: There were 554 twin pairs: 57 MC and 485 DC. We found no difference in the decrease of pH (p = 0.912) and Apgar (p = 0.609) in relation to increasing time interval. Neonatal unit (NICU) admissions did not differ (p = 0.167). Apgar ≤ 7 (p <0.001) and pH ≤ 7.20 (p = 0.002) increased first twin, whereas first (p = 0.001) or second (p <0.001) twin Apgar ≤ 7 and second twin pH ≤ 7.00 (p = 0.003) increased second twin risk of NICU admission. Conclusions: Increasing delivery interval was associated with a significant decrease in pH and Apgar, but there was no difference between MC and DC twins. Low Apgar of the first twin increased the risk of second twin NICU admission.
Journal of Maternal - Fetal and Neonatal Medicine, 2013, Vol 27, Issue 1, p. 42-47