Therapeutic cerclage may be more efficacious in women who develop cervical insufficiency after a term delivery

Factors Associated with Spontaneous Preterm Birth after Ultrasound-Indicated Cerclage

Ultrasound-indicated cerclage (UIC) is recommended to prevent spontaneous preterm birth (sPTB) in women with a short cervix at mid-trimester and a history of PTB. We assessed the factors related to sPTB after UIC and determined the corresponding risks. This retrospective cohort study was conducted at a university hospital. UIC was performed between 15 and 26 weeks of gestation in women with a cervical length of <2.5 cm. Univariate and multivariate analyses were used to examine factors associated with sPTB after UIC. An earlier gestational age and shorter cervical length at UIC were associated with sPTB after UIC. While PTB history was not associated with an increased risk of sPTB, it did increase the risk of repeat cerclage after UIC. Higher levels of preoperative serum inflammatory markers and obesity significantly increased the risk of sPTB after UIC. These findings provide helpful guidance for patient counseling and management in predicting the delivery timing after UIC in women with a short cervix in the mid-trimester.

Degree of expression of inflammatory proteins in the amniotic cavity, but not prior obstetric history, is associated with the risk severity for spontaneous preterm birth after rescue cerclage for cervical insufficiency

PROBLEM

To examine whether the severity of spontaneous preterm birth (SPTB) risk after rescue cerclage for acute cervical insufficiency (CI) is linked to the degree of inflammatory response in the amniotic fluid (AF) based on the concentrations of various inflammatory proteins and prior obstetric history.

METHOD OF STUDY

We conducted a retrospective cohort study of 65 singleton pregnant women (17-25 weeks) who underwent rescue cerclage following the diagnosis of acute CI and were subjected to amniocentesis. EN-RAGE, IL-6, IL-8, and IP-10 as inflammatory mediators and kallistatin, MMP-2/8, and uPA as extracellular matrix remodeling-related molecules were assayed in the AF using ELISA. The level of each inflammatory mediator was divided into quartiles.

RESULTS

Intra-amniotic inflammation (IAI; AF IL-6 level ≥2.6 ng/mL) was independently associated with SPTB after cerclage placement. The odds of SPTB at < 32 weeks, even after adjusting for confounders, increased significantly with each increasing quartile of baseline AF levels for each inflammatory mediator (p for trend < .05). Kaplan-Meier survival curves showed that the cerclage-to-delivery intervals were significantly shorter as the quartiles of AF EN-RAGE and MMP-8 increased (log-rank test, p < .01 each). Neither previous term birth nor prior PTB was associated with SPTB risk or cerclage-to-delivery interval after rescue cerclage. Multiparous women who experience CI after term birth showed significantly elevated levels of MMP-8 and reduced kallistatin levels in the AF.

CONCLUSION

In patients with CI, SPTB risk (especially risk severity) after rescue cerclage is associated with the degree of the inflammatory response in AF as well as the presence of IAI but not with prior obstetric history.

A new quantification system for assessing the degree of acute cervical insufficiency based on physical and sonographic examination

OBJECTIVES

Acute cervical insufficiency accounts for 10-25 % of all mid-trimester pregnancy losses. However, the definition and description for the degree of acute cervical insufficiency were obscure and different among the many studies. The aim of this study was to suggest a new 4-digit quantification system and to evaluate the outcome according to the new system in women with acute cervical insufficiency.

STUDY DESIGN

A retrospective cohort study was conducted in patients with acute cervical insufficiency who underwent physical examination indicated cervical cerclage. Acute cervical insufficiency was defined as painless external os dilation with prolapsed and/or visible membranes on speculum examination. The status of fetal membranes was described using two values: 1) size of the prolapsed membrane (P, measured using ultrasound); and 2) size of visible fetal membranes (M, evaluated by speculum examination). The status of cervix was described using two values: 1) dilatation of the narrowest os (O, measured by ultrasound); and 2) functional cervical length (C, measured by ultrasound). The patients were divided into 3 groups as follows: Stage I, patients with visible fetal membranes (M > 0) but with a remaining functional cervix (C > 0) (N = 7); stage II, those with visible fetal membranes (M > 0) and a functional cervical length of 0 but without prolapsed membranes (P = 0) (N = 33); and stage III, those with prolapsed membranes (P > 0) (N = 40).

RESULTS

1) Patients who delivered before 34 weeks of gestation had a significantly lower median gestational age at cerclage operation and a significantly higher median P, M, C values than those who delivered at or beyond 34 weeks of gestation(P < 0.01 for gestational age at operation, P and M values; P < 0.05 for C value); 2) The higher the stage based on PMOC quantification system, the greater the risk of preterm delivery before <24, <32, <34, and <37 weeks of gestation (P < 0.001 for all); 3) The neonatal survival rate was 100 % (7/7) for stage I, 93.9 % (31/33) for stage II, and 60 % (24/40) for stage III.

CONCLUSION

The PMOC system was a simple method to describe the individualized conditions and to predict the risk of preterm births in all spectrums of acute cervical insufficiency.

Patients with acute cervical insufficiency without intra-amniotic infection/inflammation treated with cerclage have a good prognosis

Background The frequency of intra-amniotic infection/inflammation (IAI/I) in patients with midtrimester cervical insufficiency is up to 50%. Our purpose was to determine the perinatal outcomes of cervical cerclage in patients with acute cervical insufficiency with bulging membranes, and to compare the admission-to-delivery interval and pregnancy outcomes according to the results of amniotic fluid (AF) analysis and cerclage placement. Methods This was a retrospective cohort study including singleton pregnancies with cervical insufficiency between 15 and 26.9 weeks in two tertiary health centers. IAI/I was defined when at least one of the following criteria was present in AF: (a) a white blood cell (WBC) count >50 cells/mm3; (b) glucose concentration <14 mg/dL; and/or (c) a Gram stain positive for bacteria. Three different groups were compared: (1) absence of IAI/I with placement of a cerclage; (2) amniocentesis not performed with placement of a cerclage; and (3) IAI/I with or without a cerclage. Results Seventy patients underwent an amniocentesis to rule out IAI/I. The prevalence of IAI/I was 19%. Forty-seven patients underwent a cerclage. Patients with a cerclage had a longer median admission-to-delivery interval (33 vs. 2 days; P < 0.001) and delivered at a higher median gestational age (27.4 vs. 22.6 weeks; P = 0.001) than those without a cerclage. The neonatal survival rate in the cerclage group was 62% vs. 23% in those without a cerclage (P = 0.01). Patients without IAI/I who underwent a cerclage had a longer median admission-to-delivery interval (43 vs. 1 day; P < 0.001), delivered at a higher median gestational age (28 vs. 22.1 weeks; P = 0.001) and had a higher neonatal survival rate (67% vs. 8%; P < 0.001) than those with IAI/I. Conclusion The pregnancy outcomes of patients with midtrimester cervical insufficiency and bulging membranes are poor as they have a high prevalence of IAI/I. Therefore, a pre-operative amniocentesis is key to identify the best candidates for the subsequent placement of a cerclage.

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.