Physical Examination-Indicated Cerclage in Singleton and Twin Pregnancies and Risk Factors for Predicting Preterm Birth < 28 Weeks

We compare the outcomes of physical examination-indicated cerclage (PEIC) between singleton and twin pregnancies and analyze predictive factors for preterm birth < 28 weeks of gestation. Patients who underwent PEIC at our center were reviewed. We compared perinatal outcomes between singleton and twin pregnancies. The primary outcome was delivery before 28 weeks of gestation. Also, we analyzed perioperative clinical, laboratory, and sonographic findings to determine the risk factors for predicting preterm birth < 28 weeks. The rate of preterm birth < 28 weeks was not significantly different. Also, neonatal outcomes were not different. Also, we compared the outcomes according to GA (gestational age) at delivery before (Group A) or after (Group B) 28 weeks, which is the primary outcome. In perioperative findings, group A was likely to have more advanced cervical dilatation, bulging membranes into the vagina, positive fFN or IGFBP-1, and shorter postoperative CL (cervical length) than group B. Also, positive fFN or IGFBP-1 and postoperative CL < 21.6 mm were independently associated with a higher risk of preterm birth < 28 weeks. These findings provide the effectiveness of PEIC with twin pregnancy as well as singleton pregnancy and helpful predictive methods that might effectively identify women at high risk of preterm birth < 28 weeks following PEIC.

Physical examination-indicated cerclage in twin pregnancies compared with singleton pregnancies

OBJECTIVE

The aim of this study was to compare pregnancy outcomes of physical examination-indicated cerclage in twin and singleton pregnancies with bulging membranes.

METHODS

All women with bulging membranes in the second trimester of pregnancy who were admitted to La Fe University and Polytechnic Hospital from January 2009 to January 2022 were included. A total of 128 participants were enrolled, 102 singleton pregnancies and 26 twin pregnancies. All patients underwent an amniocentesis to rule out intra-amniotic inflammation (IL-6 < 2.6 ng/mL). Cerclage was placed in the absence of intra-amniotic inflammation.

RESULTS

Compared with singleton gestations, twin pregnancies displayed a significantly higher prevalence of nulliparity and assisted reproductive techniques. The incidence of intra-amniotic inflammation/infection was similar in both groups (68.62% in singleton vs. 65.38% in twin pregnancies). The average gestational age of delivery without cerclage in singleton gestations was 23.83 weeks (95% CI 22.82-24.84) and in twin pregnancies, it was 23.69 weeks (95% CI 21.8-25.57). The average gestational age at delivery among patients with cerclage was 37.27 weeks (95% CI 35.35-39.19) in singleton gestations and 36 weeks (95% CI 33.51-38.63) in twin pregnancies, with no significant differences. Time from diagnosis to delivery in patients with IL-6 < 2.6 ng/mL was 79.88 days, and in those with IL > 2.6 ng/mL was 10.87 days. Gestational age at delivery was significantly higher in both singleton and twin pregnancies with cerclage, compared with those without cerclage (log-rank p < .001).

CONCLUSIONS

Singleton and twin pregnancies with bulging membranes behave similarly when cerclage is placed in the absence of intraamniotic inflammation/infection.

Effects of Amnioreduction before Physical Examination-Indicated Cerclage on Pregnancy Outcomes: A Propensity Score Matched Study

This study investigated the effects of amnioreduction before physical examination-indicated cerclage on pregnancy outcomes using a propensity score matching analysis. This multicenter retrospective cohort study included women who underwent cerclage operations due to painless cervical dilation in the second trimester (14-28 weeks). The primary outcome was the time from operation until delivery. Secondary outcomes included preterm birth rate and neonatal outcomes. Primary and secondary outcomes were compared between those with amnioreduction and those without amnioreduction. Of 103 women, 31 received preoperative amnioreduction (amnioreduction group) and 72 women did not (no-amnioreduction group). Since there were differences in baseline characteristics and preoperative ultrasound findings between the two groups, we matched 25 women with amnioreduction and 25 women without amnioreduction using a propensity score. In the matched cohort, the amnioreduction group showed a shorter time from operation to delivery than the group without amnioreduction and the hazard ratio of amnioreduction was 2.5 (95% confidence interval; 1.4-4.7). In addition, the preterm birth rate before 28 weeks of gestation and the neonatal composite outcome were higher in the amnioreduction group than that in the group without amnioreduction. Amnioreduction before physical examination-indicated cerclage was associated with poor pregnancy and neonatal outcomes. Therefore, careful consideration is required when performing amnioreduction before cerclage operation.

Latency to delivery in physical examination-indicated cerclage in twins is similar to that in singleton pregnancies

OBJECTIVE

To compare latency to delivery and perinatal outcomes between twin and singleton pregnancies undergoing physical examination-indicated cerclage.

METHODS

Retrospective observational study (2007-2017) of women who underwent physical examination-indicated cerclage at the Hospital Clinic of Barcelona. Primary outcomes were latency from cerclage to delivery and gestational age at delivery. Secondary outcomes included: neonatal morbidity and mortality, preterm prelabor rupture of membranes, clinical chorioamnionitis and cerclage displacement. Wilcoxon-test and χ² test were used to compare continuous and categorical variables.

RESULTS

Sixty women were included (17 twins and 43 singletons). There were no differences in gestational age at cerclage or presence of bulging membranes between groups. Median (25th;75th percentile) gestational age at delivery was 27.1 (24.5;32.3) weeks in the twin group and 27.6 (25.3;35.3) weeks in the singleton group (P = 0.594). There were no statistically significant differences in latency from cervical cerclage to delivery between the two groups (43 days [21;64] vs. 29 days [16;76], respectively; P = 0.938). There were no differences in neonatal mortality (2/26 [7.7%] vs. 1/33 [3.1%]; P = 0.578) or in composite neonatal morbidity (14 [53.9%] vs. 14 [42.4%]; P = 0.283) between groups, respectively.

CONCLUSION

These results suggest that physical examination-indicated cerclage placement in twins could prolong latency to delivery similarly to singleton pregnancies.

Incidences of complications associated with cervical cerclage by indication of the procedure

AIM

To investigate the incidence of complications associated with cervical cerclage by indication.

METHODS

This was a retrospective cohort study of women with singleton pregnancies who underwent cervical cerclage in a single perinatal center between 2008 and 2019. The participants were divided into three groups according to indication: history-indicated cerclage (HIC) group, ultrasound-indicated cerclage (UIC) group, and physical examination-indicated cerclage (PEIC) group. The incidences of perioperative complications within 2 weeks after the procedure, including intraoperative rupture of membranes, intraoperative bleeding, anesthesia complications, clinical chorioamnionitis, premature rupture of membranes (PROM), preterm delivery, and displacement of the suture, and those of peripartum complications, including difficult suture removal and cervical laceration, for each group were compared using Fisher's exact test or Pearson's chi-square test. Factors associated with severe adverse event, defined as PROM or delivery within 2 weeks after the procedure, were analyzed using multivariate logistic regression analysis.

RESULTS

A total of 279 women (HIC, 38; UIC, 96; PEIC, 145) were enrolled. The incidence of perioperative complications was different among the three groups (7.9%, 10.4%, and 27.6%, respectively; p < 0.01), whereas that of peripartum complications was similar (18.4%, 11.5%, and 12.4%, respectively; p = 0.54). Severe adverse events occurred only in PEIC group, with an incidence of 18.6%. The associated factor for severe adverse events in PEIC group was prolapsed membranes into the vagina.

CONCLUSIONS

Incidences of perioperative complications of cerclage differed among the indications. Women who underwent PEIC had higher risk of severe adverse events, especially when accompanied with prolapsed membranes into the vagina.

Outcomes of physical examination-indicated cerclage in twin pregnancies with acute cervical insufficiency compared to singleton pregnancies

Objectives To compare pregnancy outcomes of physical examination-indicated cerclage in twin pregnancies with acute cervical insufficiency with that of singletons. Methods This retrospective cohort study included 88 consecutive women (17 twins and 71 singletons) who had undergone physical examination-indicated cerclage because of acute cervical insufficiency (defined as painless cervical dilation with (1) prolapsed and/or visible membranes at the external cervical os on speculum examination and (2) a functional cervical length of zero on transvaginal ultrasound) between 160/7 and 236/7 weeks. The primary outcome measure was preterm delivery <34 weeks. Results (1) The frequency of preterm delivery <34 weeks was not significantly different between the two groups [twins, 56% (9/16) vs. singleton, 53% (37/70), P>0.999]. (2) The perinatal mortality was 21% (7/34) in twins and 32% (23/71) in singletons. (3) The median gestational age at delivery for twin pregnancies was 31.0 weeks (IQR, 22.6-36.5 weeks), which was similar to that of singleton pregnancies (median 32.4 weeks; IQR 22.3-38.3 weeks). (4) There were no significant differences in preterm delivery before 28 and 32 weeks, interval from cerclage to delivery within 1, 2, 4 and 8 weeks and neonatal morbidities between the two groups. Conclusion The obstetric and neonatal outcomes of physical examination-indicated cerclage in twin pregnancies were comparable to those in singleton pregnancies.

Amniotic fluid HIF1α and exosomal HIF1α in cervical insufficiency patients with physical examination-indicated cerclage

OBJECTIVE

Hypoxia inducible factor 1α (HIF1α) has been reported to activate inflammatory cascade. Recently, exosomes have been known to have pivotal roles in intercellular communication. The aim of this study was to compare the concentration of amniotic fluid (AF) HIF1α, exosomal HIF1α, and inflammatory cytokines such as interleukin 1α (IL1α), interleukin 1β (IL1β), interleukin 6 (IL6), and tumor necrosis factor α (TNFα) between physical examination-indicated cerclage (PEIC) and control group. We also investigated the associations between biomarkers and amniocentesis-to-delivery interval and the correlations of inflammatory cytokines, HIF1α, and exosomal HIF1α.

METHODS

Case-control study was performed. Cases are defined as 16 patients who underwent PEIC and controls are 19 women who underwent amniocentesis for confirming chromosomal abnormalities. The concentration of IL1α, IL1β, IL6, TNFα, HIF1α, and exosomal HIF1α were measured using enzyme-linked immunosorbent assay (ELISA). Exosomes were confirmed by tumor susceptibility Gene 101 (TSG 101) and transmission electron microscopy (TEM).

RESULTS

The mean HIF1α in PEIC group was higher than control group (PEIC, 15.03 ± 9.60-pg/mL versus control, 2.96 ± 1.99 pg/mL; p < .01). There were significant differences in inflammatory cytokines between two groups. A significant difference in exosomal HIF1α was shown between two groups (PEIC, 27.97 ± 28.61-µg/mL versus control, 12.42 ± 8.20 µg/mL; p < .01). HIF1α, IL1α, IL6, TNFα, and exosomal HIF1α showed significantly negative association with cerclage-to-delivery interval. However, IL1β was not associated with cerclage-to-delivery interval. HIF1α was positively correlated with exosomal HIF1α (rho = 0.93, p < .01). Both HIF1α and exosomal HIF1α were significantly associated with TNFα (rho = 0.94, p < .01; rho = 0.97, p < .01). Both HIF-1α and exosomal HIF1α had positive correlation with IL1α (rho = 0.96, p < .01; rho = 0.91, p < .01). However, IL1β showed no correlations with HIF1α and exosomal HIF1α. A positive correlation between HIF-1α and IL6 was observed (rho = 0.58, p = .01.) Exosomal HIF1α also had correlation with IL6 (rho = 0.52, p = .03).

CONCLUSIONS

This study demonstrated that amniotic fluid (AF) HIF1α and AF exosomal HIF1α were higher in physical examination-indicated cerclage (PEIC) group than control group. AF HIF1α and AF exosomal HIF1α were associated with shorter amniocentesis-to-delivery interval. More importantly, they had positive correlations with AF inflammatory cytokines such as IL1α, IL6, and TNFα. Our results may indicate that AF HIF1α and AF exosomes interact with AF inflammatory cytokines and contribute inflammatory cascade in complicated pregnancies.