Cervical cerclage is advised in an antenatal woman with a prior preterm bih if the cervical length measures

Cervical length screening is now recommended by both the American College of Obstetricians and Gynecologists (2016b) and the Society for Maternal-Fetal Medicine (2015) for women with prior preterm bih.Between 16 and 24 weeks' gestation, sonographic cervical measurement is completed every 2 weeks.If an initial or subsequent cervical length is 25 to 29 mm, then a weekly interval is considered.If the cervical length measures <25 mm, cerclage is offered to this group of women. Notably, for women without history of preterm bih but with a sho cervix incidentally identified sonographically, progesterone therapy is offered instead of cerclage.Reference: William's Obstetrics; 25th edition; Chapter 18; Aboion