This paper is part of a supplement that represents a collection of COVID-related articles selected for publication by the editors of AJOG MFM without additional financial support.

Background : Delayed interval delivery is a rare practice aiming at prolonging gestation for the second twin in case of pre-viable birth of twin one. Our objective was to identify factors related to successful delayed delivery of the second twin, among cases in which the interval after delivery of the first twin was above 24 hours. Method : A descriptive, retrospective and multicenter study of all delayed interval deliveries in dichorionic twins in 4 perinatal centers in Paris over a 14-year period. Results : In 13 cases of delayed interval delivery, delivery of twin 1 was at a median of 18 weeks' gestation (range 14WG+2days to 24WG), and none survived. Delivery of the second twin occurred at a median of 25 weeks' gestation +3 days, 51 days after twin 1 (range 13 to 138 days). Seven of the 13 second twins (54%) survived. There were 5 cases of chorioamnionitis and 1 case of maternal disseminated intravascular coagulation. Poor outcome was not significantly associated with the gestational age, presentation for PPROM or inflammatory markers (C-reactive protein and white blood cell count) at the time of delivery of twin 1. Conclusion : Delayed-interval delivery of the second twin may prolong pregnancy and lead the second twin child to a viable term of birth; but carries a risk of maternal complications.