N., Abdelaal, Sanad Z., Shaheen A., Hamza H., and Al Halaby A. 2017. “Effect of Vaginal Progesterone in Combination With Cervical Cerclage on Improved Gestational Age and Perinatal Outcome in Twin Pregnancy: A Prospective Randomized Study”. International Journal of Reproduction, Contraception, Obstetrics and Gynecology 6 (8):3224-29. https://doi.org/10.18203/2320-1770.ijrcog20173442.