“…Socio-biological variables like low maternal age, 3 marital status, race and ethnicity, 4 (more common in African-American women), cigarette smoking, 5 environmental stress, 6 short interpregnancy interval, 7 alcohol, coffee, and substance abuse. 8 Past obstetric history like previous preterm delivery, 9 previous abortion, 10 multiple dilatation and curettage, 11 cervical surgery like cone biopsy, large loop excision of transformation zone (LLETZ). 12 Complications of current pregnancy like elective preterm birth for a number of maternal and foetal reasons such as preeclampsia, placenta previa, abruption placenta, 4 multiple gestations due to Artificial reproductive techniques and infection.…”