ABSTRACT
A short cervix during pregnancy offers less resistance to ascending infection, which is related to the occurrence of preterm birth, preterm premature rupture of the membranes, and mid-trimester abortion. All these events significantly increase the incidence of perinatal mortality and morbidity. Cervical cerclage is a procedure used to increase the functional length of the cervix during pregnancy, by placement of a tape at the level of the internal os to support the cervical musculature. Much controversy is present about the value of cervical cerclage in improving perinatal outcome. The use of a braided synthetic material, that will significantly change the bacterial milieu in the upper vagina and cervix, might in itself play a role in promoting infection, and might contribute to this controversy. On the other hand, the use of a monofilament suture material as Prolene, might obviate the changes in the bacterial milieu of the high vagina after the procedure, and might help improve the perinatal outcome. To identify the microbiological changes of the cervico-vaginal flora in women undergoing modified Shirodkar operation using two different suture materials, and to compare the pregnancy outcomes as an indicator of operation effectiveness. A randomised controlled trail was conducted at Ain Shams University Maternity Hospital [ASUMH] from September 2000 through February 2002. Bacteriological indicators of infection [Number and type of colony forming units]; fetal salvage ratio; prematurity ratio. 44 Cases with clinical and/or dynamic ultrasonographic criteria of cervcial incompetence underwent cervical cerclage operation using either Prolene suture or Nylon-tape according to the modified Schirodkar technique. 4 cases dropped out. The rest [40 cases] were followed up till they ended their pregnancy spontaneously. Bacteriological swabs were obtained pre- and 4 weeks post operatively and aerobic and anaerobic cultures were performed and analysed. No difference was observed between the two groups in any of the major confounding variables. The Prolene group had statistically significantly less post-operative bacterial colonizaton compared to the Nylon-tape group. The Prolene group showed better fetal-salvage and prematurity ratois; the results reaching statistical significance. Elective cervical cerclage by modified Shirodkar technique at 12 to 18 weeks' gestation using Prolene suture improves the fetal salvage as well as the prematurity ratio in patients at risk of fetal wastage due to cervical incompetence. Prolene suture was statistically significantly superior to Nylon tape as regards the microbiological and perinatal outcome measures. Intervention on the basis of dynamic ultrasono graphic parameters was related to a better fetal survival outcome