Impaired Neonatal Outcome after Emergency Cerclage Adds Controversy to Prolongation of Pregnancy

Effectiveness and pregnancy outcomes of ultrasound-indicated and physical examination-indicated cervical cerclage: a retrospective study from a single centre

OBJECTIVE

Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality worldwide, and cervical incompetence (CIC) is a significant contribution. Cervical cerclage (CC) is an effective obstetric intervention. However, many clinical factors affect the success rate of surgery. The objective was to investigate and compare the pregnancy and neonatal outcomes of patients who underwent ultrasound- and physical examination-indicated cervical cerclage and to explore the influencing factors of preterm delivery before 34 weeks.

METHODS

The sociodemographic characteristics and clinical data of patients with a diagnosis of cervical incompetence who underwent ultrasound- and physical examination-indicated transvaginal cervical cerclage at Nanjing Maternal and Child Health Hospital from January 2020 to December 2022 were retrospectively analyzed. The pregnancy and neonatal outcomes of the patients were evaluated. Continuous variables were compared using Student's t test (for normally distributed data) or the Mann-Whitney U test (for nonnormally distributed data). Categorical variables were analysed using the chi-square test or Fisher's exact test. Additionally, logistic regression analyses and receiver operating characteristic curves were used to evaluate the associations of inflammatory markers with maternal and neonatal outcomes.

RESULTS

This study included 141 participants who underwent cervical cerclage, including 71 with ultrasound-indicated cerclage and 70 with physical examination-indicated cerclage. Compared to those in the ultrasound-indicated cerclage group, the duration from cerclage to delivery, birth weight, and APGAR score in the physical examination-indicated cerclage group were significantly lower, and the rates of delivery at < 28 weeks, < 32 weeks, < 34 weeks, and < 37 weeks of gestation and neonatal mortality were significantly higher (all P < 0.05). Compared to those in the physical ultrasound-indicated cerclage group, in the physical examination-indicated cerclage group, maternal blood inflammatory markers, such as C-reactive protein (CRP), the systemic immune-inflammation index (SII) and the systemic inflammation response index (SIRI) were significantly higher (P < 0.05). Additionally, maternal blood inflammatory markers, such as the CRP, white blood cell count, platelet to lymphocyte ratio (PLR), SII, and SIRI were significantly higher in the group with delivery before 34 weeks of gestation. Furthermore, the results demonstrated that twin pregnancy had the highest OR for preterm delivery before 34 weeks of gestation (OR = 3.829; 95% CI 1.413-10.373; P = 0.008), as well as the following: the SII level (OR = 1.001; 95% CI 1.000-1.002; P = 0.003) and CRP level (OR = 1.083; 95% CI 1.038-1.131; P = 0.022). The risk factors for preterm delivery before 34 weeks of gestation were twin gestation, an increased SII level and an increased CRP level, which had good combined predictive value.

CONCLUSION

In patients with cervical insufficiency, ultrasound-indicated cervical cerclage appears to lead to better pregnancy outcomes than physical examination-indicated cerclage. Twin pregnancy and maternal blood inflammatory markers, such as the CRP level and the SII, are associated with preterm delivery before 34 weeks of gestation.

The efficacy of emergency cervical cerclage in singleton and twin pregnancies: a systematic review with meta-analysis

OBJECTIVE

An emergency (rescue) cervical cerclage can be offered to pregnant women presenting with dilatation and prolapsed membranes in the second trimester of pregnancy because of cervical insufficiency. This study aimed to investigate the effectiveness of an emergency cerclage in both singleton and twin pregnancies in the prevention of extreme premature birth.

DATA SOURCES

We performed a systematic literature search in PubMed and Embase from inception to June 2022 for transvaginal cervical emergency cerclages.

STUDY ELIGIBILITY CRITERIA

All studies on transvaginal cervical emergency cerclages with at least 5 patients and reporting survival were included.

METHODS

Included studies were assessed for quality and risk of bias with an adjusted Quality In Prognosis Studies tool. Random-effects meta-analyses and meta-regressions were performed for the primary outcome: survival.

RESULTS

Our search yielded 96 studies, incorporating 3239 women, including 14 studies with an expectant management control group, incorporating 746 women. Overall survival after cervical emergency cerclage was 74%, with a fetal survival of 88% and neonatal survival of 90%. Singleton and twin pregnancies showed similar survival, with a pregnancy prolongation of 52 and 37 days and a gestational age at delivery of 30 and 28 weeks, respectively. Meta-regression analyses indicated a significant inverse association between mean gestational age at diagnosis and pregnancy prolongation and no association between dilatation or gestational age at diagnosis and gestational age at delivery. Compared with expectant management, emergency cerclage significantly increased overall survival by 43%, fetal survival by 17% and neonatal survival by 22%, along with a significant pregnancy prolongation of 37 days and reduction in delivery at <28 weeks of gestation of 55%. These effects were more profound in singleton pregnancies than in twin pregnancies.

CONCLUSION

This systematic review indicates that, in pregnancies threatened by extreme premature birth because of cervical insufficiency, emergency cerclage leads to significantly higher survival, accompanied by significant pregnancy prolongation and reduction in delivery at <28 weeks of gestation, compared with expectant management. The mean gestational age at delivery was 30 weeks, independent of dilatation or gestational age at diagnosis. Survival was similar for singleton and twin pregnancies, implying that emergency cerclage should be considered in both.

A retrospective study analyzing indications and outcomes of mid-trimester emergency cervical cerclage in a tertiary care perinatal centre over half a decade

We studied the indications, success rate, perinatal outcomes and maternal complications following mid-trimester emergency cervical cerclage. All women undergoing mid-trimester emergency cerclage at our centre during 2014-2019 were included in this retrospective study.There were 46 women in our cohort. Mean cervical length was 1.5 cm (SD ± 0.7), and 52.1% of them had bulging membranes. The mean gestational age at cerclage was 23.35 weeks (SD ± 3.341). Three were loss to follow up.Out of 43 pregnancies (23 singletons and 20 twins) analyzed, 37/43, 86.4% had livebirths. Success rate in the singletons and twins were 91.3% and 80% respectively. Maternal complications were seen in 56.5% of patients. Composite neonatal morbidity was significantly more in the twin group (p-value 0.04).Overall live birth rate was 86.4% with similar success rates in singleton and multiple pregnancies. Although, evidence for beneficial effect of prophylactic cerclage in multiple gestation is lacking, emergency cerclage may have a role in twin gestation.

Maternal smoking as an independent risk factor for the development of severe retinopathy of prematurity in very preterm infants

BACKGROUND/OBJECTIVES

Retinopathy of prematurity (ROP) is a severe neonatal complication potentially leading to visual impairment and blindness. Known risk factors include preterm birth, low birth weight and respiratory support. Limited and contradictory data exist on the risk of maternal smoking during pregnancy on the development of ROP. This study aims to investigate smoking as an independent risk factor for the development of severe ROP (≥stage 3).

SUBJECTS/METHODS

This is a single centre retrospective case-control study of prospectively collected clinical data of infants born before 32 weeks of gestation between 2001 and 2012 at a tertiary care university hospital. The association between maternal smoking during pregnancy and the development of severe ROP was analyzed by multivariate logistic regression.

RESULTS

In total, n = 751 infants born < 32 weeks of gestation were included in this study. In total, 52.9% (n = 397) were diagnosed with ROP and 10.8% (n = 81) developed ROP ≥ stage 3. In total, 8.4% (n = 63) mothers presented with a history of smoking during pregnancy, which was associated to a higher rate of ROP (OR 2.59, 95% CI 1.10-6.12). Low gestational age, low birth weight and prolonged respiratory support were confirmed as independent risk factors for the development of severe ROP.

CONCLUSIONS

To date, this is the largest study evaluating the effect of maternal smoking on the development of ROP. Maternal smoking during pregnancy is identified as an independent risk factor for the development of severe ROP in preterm infants born < 32 weeks of gestation.

Antenatal exposure to fenoterol is not associated with the development of retinopathy of prematurity in infants born before 32 weeks of gestation

PURPOSE

Despite safety concerns, β₂-sympathomimetics are still widely used as tocolytic agents. β-Blockers in turn are used to treat vasculo-proliferative diseases of the newborn such as retinopathy of prematurity (ROP), which may lead to visual impairment and blindness. The scope of this study was to investigate whether antenatal exposure to the β₂-sympathomimetic fenoterol contributes to the development of ROP.

METHODS

For this single-center retrospective case-control study of prospectively collected clinical data, all infants born before 32 weeks of gestation between 2001 and 2012 were included. The association of prenatal exposure to fenoterol and the development of ROP were analyzed by multivariate logistic regression.

RESULTS

n = 1134 infants < 32 weeks of gestation were screened for eligibility, out of which n = 722 met the inclusion criteria. Exposure to fenoterol (n = 505) was not associated with a higher rate of ROP (OR 0.721, 95% CI 0.463-1.122). Further, duration of exposure (days) did not alter the incidence of ROP (OR 1.001, 95% CI 0.986-1.016). Frequency distribution of different ROP stages and the need for therapeutic intervention was also not affected by prenatal exposure to fenoterol. Risk factors for the development of ROP like low birth weight, low gestational age, prolonged respiratory support and multiple gestation were confirmed in our large study cohort.

CONCLUSION

β₂-Sympathomimetic tocolysis does not increase the rate of ROP in premature infants born < 32 weeks of gestation. Our results render fenoterol a safe tocolytic agent regarding neonatal ROP development.

Methods for a similarity measure for clinical attributes based on survival data analysis

Background

Case-based reasoning is a proven method that relies on learned cases from the past for decision support of a new case. The accuracy of such a system depends on the applied similarity measure, which quantifies the similarity between two cases. This work proposes a collection of methods for similarity measures especially for comparison of clinical cases based on survival data, as they are available for example from clinical trials.

Methods

Our approach is intended to be used in scenarios, where it is of interest to use longitudinal data, such as survival data, for a case-based reasoning approach. This might be especially important, where uncertainty about the ideal therapy decision exists. The collection of methods consists of definitions of the local similarity of nominal as well as numeric attributes, a calculation of attribute weights, a feature selection method and finally a global similarity measure. All of them use survival time (consisting of survival status and overall survival) as a reference of similarity. As a baseline, we calculate a survival function for each value of any given clinical attribute.

Results

We define the similarity between values of the same attribute by putting the estimated survival functions in relation to each other. Finally, we quantify the similarity by determining the area between corresponding curves of survival functions. The proposed global similarity measure is designed especially for cases from randomized clinical trials or other collections of clinical data with survival information. Overall survival can be considered as an eligible and alternative solution for similarity calculations. It is especially useful, when similarity measures that depend on the classic solution-describing attribute “applied therapy” are not applicable. This is often the case for data from clinical trials containing randomized arms.

Conclusions

In silico evaluation scenarios showed that the mean accuracy of biomarker detection in k = 10 most similar cases is higher (0.909–0.998) than for competing similarity measures, such as Heterogeneous Euclidian-Overlap Metric (0.657–0.831) and Discretized Value Difference Metric (0.535–0.671). The weight calculation method showed a more than six times (6.59–6.95) higher weight for biomarker attributes over non-biomarker attributes. These results suggest that the similarity measure described here is suitable for applications based on survival data.

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.

Prospective observational study of vaginal microbiota pre- and post-rescue cervical cerclage

OBJECTIVE

To investigate the relation between vaginal microbiota composition and outcome of rescue cervical cerclage.

DESIGN

Prospective observational study.

SETTING

Queen Charlotte's and Chelsea Hospital, London.

POPULATION

Twenty singleton pregnancies undergoing a rescue cervical cerclage.

METHODS

Vaginal microbiota composition was analysed in women presenting with a dilated cervix and exposed fetal membranes before and 10 days following rescue cervical cerclage and was correlated with clinical outcomes.

MAIN OUTCOME MEASURES

Composition of vaginal bacteria was characterised by culture-independent next generation sequencing. Successful cerclage was defined as that resulting in the birth of a neonate discharged from hospital without morbidity. Unsuccessful cerclage was defined as procedures culminating in miscarriage, intrauterine death, neonatal death or significant neonatal morbidity.

RESULTS

Reduced Lactobacillus spp. relative abundance was observed in 40% of cases prior to rescue cerclage compared with 10% of gestation age-matched controls (8/20, 40% versus 3/30, 10%, P = 0.017). Gardnerella vaginalis was over-represented in women presenting with symptoms (3/7, 43% versus 0/13, 0%, P = 0.03, linear discriminant analysis, LDA (log 10) and cases culminating in miscarriage (3/6, 50% versus 0/14, 0%, P = 0.017). In the majority of cases (10/14, 71%) bacterial composition was unchanged following cerclage insertion and perioperative interventions.

CONCLUSIONS

Reduced relative abundance of Lactobacillus spp. is associated with premature cervical dilation, whereas high levels of G. vaginalis are associated with unsuccessful rescue cerclage cases. The insertion of a rescue cerclage does not affect the underlying bacterial composition in the majority of cases.

TWEETABLE ABSTRACT

Preterm cervical dilatation associates with reduced Lactobacillus spp. Presence of Gardnerella vaginalis predicts rescue cerclage failure.

Vaginal Cerclage: Preoperative, Intraoperative, and Postoperative Management

The role of the cerclage procedure has expanded from its initial application as treatment or prevention of cervical insufficiency to prevention of recurrent spontaneous preterm birth. Although recent prospective studies have clarified the indications for cerclage, additional prospective studies are needed to help define optimal perioperative management. Herein, we review the current data to provide the clinician with the most evidence-based approach to managing patients who require cerclage.