Evaluation of Cervical Cerclage Timing and Perinatal Outcomes in Women with Cervical Insufficiency: A 10-Year Retrospective Study

<b>Objective:</b> The objective was to evaluate the optimal timing of cervical cerclage insertion for perinatal outcomes, such as birthweight, gestational week, and pregnancy prolongation in women with diagnosed cervical insufficiency (CI). <b>Methods:</b> This retrospective study was conducted at the 1st Department of Obstetrics and Gynaecology of the Medical University of Warsaw, over a 10-year period. Maternal and perinatal outcomes were compared between 75 women divided into three groups based on the gestational week (GW) at cerclage insertion: (1) before 18 GW (n = 31), (2) 18-22 GW (n = 31), (3) after 22 GW (n = 13). Only single pregnancies were included in the final analysis in order to maintain the homogeneity of the population. The primary outcomes included the week of delivery and pregnancy prolongation following cervical cerclage insertion. Numerous secondary outcomes were also evaluated, including neonatal mortality, need for NICU hospitalization, Apgar score, birthweight, maternal white blood cell (WBC) count and C-reactive protein (CRP) levels. <b>Results:</b> Birth week was significantly associated with GW at insertion-35.8 ± 3.8 vs. 34.8 ± 5.2 vs. 32 ± 5.7, respectively, <i>p</i> = 0.016. Moreover, statistical difference was also found regarding birthweight of the analysed groups-2723.8 ± 951.6 g vs. 2518.5 ± 1167.9 g vs. 1886.7 ± 1011.2 g, respectively, <i>p</i> < 0.001, and pregnancy prolongation following cerclage insertion 20.4 ± 4.2 vs. 14.7 ± 5.5 vs. 7.3 ± 5.7 weeks, respectively, <i>p</i> < 0.001. <b>Conclusions:</b> Earlier cerclage placement (<18 weeks) is associated with significantly improved perinatal outcomes. However, this association largely reflects the benefit of prophylactic intervention over emergency 'rescue' procedures (common in the >22-week group). The sharp decline in outcomes after 22 weeks highlights the risks of advanced cervical dilation, suggesting that clinical management should prioritize risk assessment within the prophylactic window.