The effect of chorionicity and twin-to-twin delivery time interval on short-term outcome of the second twin.

OBJECTIVES

To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin as well as to investigate the predictors of adverse outcome in both twins.

METHODS

Data included vaginally delivered twins (≥36 weeks) from Copenhagen University Hospitals (2001-2009). The association between delivery interval and adverse outcome parameters was compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression.

RESULTS

There were 554 twin pairs, of which 57 were 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 risk of NICU admission, 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.