Jamal, Shehla, and Ruchi Srivastava. 2017. “A Retrospective Analytical Study of the Epidemiology and Causes of Preterm Birth”. International Journal of Reproduction, Contraception, Obstetrics and Gynecology 6 (12):5453-57. https://doi.org/10.18203/2320-1770.ijrcog20175259.