Fig. 2

Incidence of PTD (a), spontaneous PTD (b), and pPROM (c) in the normal cytology, CIN during pregnancy and cone-length groups. a The percentage of PTD increased with cone-length. Number (percentage) of PTD in the normal cytology group, the CIN during pregnancy group and different cone length groups: normal cytology 1794/42,398 (4.2%), CIN during pregnancy 74/1380 (5.4%), <6 mm 16/212 (7.5%), 6–9 mm 77/1219 (6.3%), 10 mm 26/374 (7.0%), 11–12 mm 33/361 (9.1%), 13–15 mm 20/174 (11.5%), >15 mm 15/68 (22.1%). CIN, cervical intraepithelial neoplasia, PTD, preterm delivery. b The percentage of spontaneous PTD increased with cone-length. Number (percentage) of spontaneous PTD in the normal cytology group, the CIN during pregnancy group and different cone-length groups: normal cytology 1264 /42,398 (3.0%), CIN during pregnancy 49/1380 (3.6%), <6 mm 12/212 (5.7%), 6–9 mm 61/1219 (5.0%), 10 mm 20/374 (5.3%), 11–12 mm 27/361 (7.5%), 13–15 mm 17/174 (9.8%), >15 mm 12/68 (17.6%). CIN, cervical intraepithelial neoplasia, PTD, preterm delivery. c The percentage of pPROM was increased in women with large excisions. Number (percentage) of pPROM in the normal cytology group, the CIN during pregnancy group and different cone-length groups: normal cytology 479/42,398 (1.1%), CIN during pregnancy 20/1380 (1.4%), <6 mm 7/212 (3.3%), 6–9 mm 36/1219 (3.0%), 10 mm 10/374 (2.7%), 11–12 mm 15/361 (4.2%), 13–15 mm 6/174 (3.4%), >15 mm 9/68 (13.2%). CIN, cervical intraepithelial neoplasia; pPROM, preterm prelabor rupture of membranes