A clinical study on the incomptent internal os of the cervix

Kim, Mi Ran; Park, Eun Sun; Kang, Choon Hwa; Kim, Eun Jeong; Yang, Su Chin; Moon, Jeong Joo

Abstract

OBJECTIVE
This study was performed to evaluate the effect of cervical cerclage and the clinical characteristics in incompetent internal os of the cervix (IIOC).
METHODS
A study was conducted on 170 patients with IIOC, 199 cases of IIOC were admitted and treated with McDonald operation or modified Shirodkar operation at department of Obstetrics and Gynecology Il Sin Christian Hospital from January 1. 1994 to December 31. 1998, of this 14 cases were follow up lost, so 185 cases were analyzed.
RESULTS
1) The incidence of IIOC was 0.43%, 1 in 233 deliveries. 2) The mean age of IIOC patients was 30.54yrs old and the most frequent age group was in 30-34yrs old group (43.78%). 3) The average number of gravida and parity before operation were 4.71 and 1.62. & the success rate of operation was low at high gravida & parity. 4) The predisposing factor was previous history of dilation & curettage (43.75%), Cx. laceration after delivery (6.49%), midtrimester termination (4.32%) etc. 5) The operation methods were McDonald operation (91.35%) and modified Shirodkar operation (8.65%) & the success rate of McDonald operation and modified Shirodkar operation were 85.80% and 87.50%. 6) The successful fetal salvage rate was 85.95% and the highest success rate was 87.50% in 14-16 weeks of gestation group. 7) The more cervix dilate, the more failure occurred. 8) The causes of operation failure were premature rupture of membrane (50.00%), preterm labor (34.62%), FDIU, anomaly, APH etc. 9) The delivery
methods
after operation were vaginal delivery (65.54%), cesarean delivery (34.46%).
CONCLUSION
The 14-16th weeks of gestation group & no cervical dilatation have higher success rate indicating that early diagnosis and appropriate timing of operation is associated with a greater operation success rate.