Cervical cerclage in the second trimester of pregnancy: A historical cohort study

OBJECTIVE: The purpose of this study was to compare second-trimester transv aginal cervical cerclage with conservative management on duration of pregna ncy and perinatal outcome in patients with early or advanced cervical chang es. STUDY DESIGN: A historical cohort analysis was performed. Maternal and neon atal records between 1995 and 1999 were retrospectively reviewed for women presenting between 18 and 27 weeks of gestation with early cervical changes (length <3 cm, dilatation <2 cm, funneling of fetal membranes shown by tra nsvaginal ultrasonography) (group 1, n = 31) and for women with advanced ce rvical effacement and dilatation (cervical dilatation greater than or equal to2 cm but less than or equal to5 cm, fetal membranes visible) (group 2, n = 39). In each group, patients who underwent Shirodkar or McDonald cerclag e were compared with patients treated conservatively with bed rest. Both gr oups also received multifactorial treatment with tocolytic agents, broad-sp ectrum antibiotics, and indomethacin. Outcome variables were analyzed for s tatistical significance by parametric and nonparametric methods. RESULTS: Regardless of treatment method, patients with early cervical chang es (group 1) were given a diagnosis earlier and delivered later in pregnanc y compared with their counterparts who had advanced cervical changes (group 2) (P < .05). In both patients who underwent cerclage and those treated co nservatively, the mean birth weight among surviving infants was higher and the mean neonatal intensive care unit stay was shorter in group 1 than in g roup 2 (P < .02). However, duration of maternal hospital stay and neonatal survival rates were not different. In both groups 1 and 2, the interval fro m treatment to delivery, the mean gestational age at delivery, and mean bir th weight were increased, whereas neonatal intensive care unit stay was dec reased by cerclage treatment (P < .05). In group 1, a higher percentage of patients treated with Cerclage received antibiotics acid indomethacin than did control subjects(P < .01), whereas in group 2, the use of multifactoria l treatment was not different (P = .5). The duration of maternal hospital s tay and neonatal sur vival did not differ significantly among patients trea ted conservatively or with cerclage. CONCLUSIONS: Diagnosis of premature cervical changes by ultrasonography was correlated with treatment earlier in gestation and with a favorable impact on perinatal outcome in both patients treated with cerclage and those trea ted conservatively. Cervical cerclage was associated with an improved perin atal outcome (in comparison with conservative therapy) in women with early cervical changes detected by ultrasonography and in patients with advanced cervical dilatation and visible membranes. However, the apparent therapeuti c effect of cerclage in patients with mild cervical incompetence may be due in part to an increased use of antibiotics and indomethacin in conjunction with cerclage.