Arabin cervical pessary to prevent preterm birth in twin pregnancies with short cervix

Changes in cytokine and sequestosome-1 levels during twin pregnancy progression: Association with outcome

BACKGROUND

Twin pregnancies are associated with complications and adverse outcomes. The number of twin pregnancies has increased in the last decades, due to the use of assisted reproductive techniques and delayed childbearing. Analysis of changes that occur during twin pregnancy progression and their association with outcome will lead to improved clinical interventions.

OBJECTIVE

We evaluated if the plasma concentration of select cytokines and the level of sequestosome-1 (p62) in peripheral blood mononuclear cells (PBMCs) during each trimester of twin gestations was predictive of pregnancy outcome.

STUDY DESIGN

This prospective, observational study was conducted at Careggi University Hospital, Florence, Italy. Plasma from 82 women with twin pregnancies was collected in each trimester for measurement of interleukin (IL)-1β, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-α. The intracellular PBMC concentration of p62, a protein involved in autophagy, kinase activity and cell differentiation, was also determined.

RESULTS

IL-1β (p < 0.001), IL-6 (p < 0.001), TNF-α (p < 0.001) and p62 (p < 0.05) increased from the 1st to the 2nd to the 3rd trimester. The TNF-α level was correlated with the IL-1β concentration in the 1st and 3rd trimesters p < 0.01) and with the IL-6 concentration in each of the three trimesters (p < 0.01). The intracellular p62 level in PBMCs was negatively correlated with the concentration of IL-1β in the 2nd trimester (p < 0.05) and negatively correlated with the IL-6 level in the 3rd trimester (p < 0.05). The TNF-α level was significantly higher in the 2nd (p < 0.05) and 3rd (p < 0.001) trimester in women with a spontaneous preterm delivery. The TNF-α concentrations in the 2nd (p < 0.05) and 3rd (p < 0.01) trimester, respectively, and 3rd trimester IL-6 (p < 0.01), were negatively associated with gestational age at delivery. The concentration of IL-6 was highest in the 2nd (p < 0.05) and 3rd (p < 0.05) trimesters in women who utilized assisted reproductive technologies. An elevated IL-1β level in the 3rd trimester was associated with gestational diabetes mellitus (p < 0.05).

CONCLUSION

Variations in cytokine levels between individual women during the three trimesters of twin gestations are predictive of spontaneous preterm delivery and the onset of gestational diabetes.

Prevention of preterm birth in multiples

PURPOSE OF REVIEW

Multifetal pregnancy carries increased risk of preterm delivery, and consensus on management options to prevent early birth in this population has not been reached. This review serves to summarize the most contemporary findings on this controversial topic.

RECENT FINDINGS

Examination-indicated cerclage is effective in reducing preterm birth in twin pregnancies, whereas cerclages for other indications are less convincing. Cervical pessary may be beneficial for patients with a short cervix and in those who have had threatened preterm labor. Progesterone supplementation for multifetal gestation alone is not beneficial, but it can be considered in those with a history of prior singleton preterm birth.

SUMMARY

Interventions for preterm birth prevention in multiple gestations remain under investigation, and further data is required in order to reach consensus for this high-risk population.

Comparison of cerclage and pessary in prevention of preterm birth in twin pregnancies

Background: The preterm labor has increased in multiple pregnancies over the past 2 decades. Preterm labor has led to increase in neonatal mortality rates, long-term morbidity, respiratory distress, and neonatal infections. Thus, this study aimed at investigating the effect of cerclage versus pessary on the prevention of preterm birth in twin pregnancies.

Methods: This prospective randomized clinical trial was performed on 50 women pregnant with twins who visited Taleghani hospital in 2016-2018. Their cervical length, which was measured by transvaginal ultrasonography (TVS), was less than 30 millimeters at week 14 of pregnancy. The participants were randomly divided into 2 groups (n=25). They separately underwent cervical pessary and cerclage. McDonald's procedure was performed in cerclage group from 14 to 27 weeks. The suture material was Mersilene Ethicon 5-0 double-armed s14 needle. Ring hodge pessary was also inserted in the vagina of the participants in the pessary group. All the patients were injected 250 mg intramuscular 17 alpha-hydroxyprogesterone caproate weekly from week 16 to week 36. All statistical analyses were performed using SPSS 18 software.

Results: The results of this study showed that the mean ± standard deviation (SD) for pregnancy length of the cerclage and pessary groups were 238.6±32.4 and 223.6±16.6, respectively. Also, significant differences were found between the 2 groups (p=0.048). No significant difference was found in pregnancy (p=0.565), length of pessary/cerclage use (p=0.491), and BMI before and after delivery between the cerclage and pessary groups (p>0.05).

Conclusion: The use of cerclage in twin pregnancies is recommended to increase the length of pregnancy.

Effectiveness of cervical pessary compared to cervical cerclage with or without vaginal progesterone for the prevention of preterm birth in women with twin pregnancies and a short cervix: study protocol for a two-by-two factorial randomised clinical trial

INTRODUCTION

Women with twin pregnancies and a short cervix are at increased risk for preterm birth (PTB). Given the burden of prematurity and its attendant risks, the quest for effective interventions in twins has been an area of considerable research. Studies investigating the effectiveness of cervical cerclage, cervical pessary and vaginal progesterone in preventing PTB have yielded conflicting results. The aim of this study is to compare the effectiveness of cervical pessary and cervical cerclage with or without vaginal progesterone to prevent PTB in women with twin pregnancies and a cervical length (CL) ≤ 28 mm.

METHODS AND ANALYSIS

This multicentre, randomised clinical trial will be conducted at My Duc Hospital and My Duc Phu Nhuan Hospital, Vietnam. Asymptomatic women with twin pregnancies and a CL ≤28 mm, measured at 16-22 weeks' gestation, will be randomised in a 1:1:1:1 ratio to receive a cerclage, pessary, cerclage plus progesterone or pessary plus progesterone. Primary outcome will be PTB <34 weeks. Secondary outcomes will be maternal and neonatal complications. We preplanned a subgroup analysis according to CL from all women after randomisation and divided into four quartiles. Analysis will be conducted on an intention-to-treat basis. The rate of PTB <34 weeks' gestation in women with twin pregnancies and a cervix ≤28 mm and treated with pessary in our previous study at My Duc Hospital was 24.2%. A sample size of 340 women will be required to show or refute that cervical cerclage decreases the rate of PTB <34 weeks by 50% compared with pessary (from 24.2% to 12.1%, α level 0.05, power 80%, 5% lost to follow-up and protocol deviation). This study is not to be powered to assess interactions between interventions.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Institutional Ethics Committee of My Duc Hospital and informed patient consent was obtained before study enrolment. Results of the study will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03863613 (date of registration: 4 March 2019).

Is the Arabin Pessary really useful in preventing preterm birth? A review of literature

The aim of this review is to describe the state of the art in the use of Arabin Pessary for the prevention of spontaneous preterm birth (SPTB). We conducted a review of the literature in order to collect relevant studies concerning the efficacy of Arabin Pessary in preventing preterm birth, also considering it in addition or in comparison with other methods such as cervical cerclage or vaginal progesterone and in both singleton and twin pregnancy. Despite the large number of studies available there is not a clear consensus about the superiority of one of this methods over the others. In addition to this, although Arabin Pessary is widely used in clinical practice, no guidelines for management and use of cervical pessary during pregnancy have been assessed.

Controversies about the Secondary Prevention of Spontaneous Preterm Birth

Preterm birth is one of the major global health problems and part of the Millennium Development goals because of the associated high number of perinatal or neonatal mortality and long-term risks of neurodevelopmental and metabolic diseases. Transvaginal sonography has meanwhile been established as a screening tool for spontaneous preterm birth despite its relatively low sensitivity when considering only the cervical length. Vaginal progesterone has been shown to reduce prematurity rates below 34 weeks in a screening population of singleton pregnancies. Up to now, no positive long-term effect could be demonstrated after 2 years. It seems to have no benefit to prolong pregnancies after a period of preterm contractions and in risk patients without cervical shortening. Meta-analyses still demonstrate conflicting results dependent on quality criteria used for selection. A cerclage is only indicated in singleton pregnancies with previous spontaneous preterm birth and a combined cervical shortening in the current pregnancy. Nevertheless, the short- and long-term outcome has never been evaluated, whereas maternal complications may be increased. There is no evidence for a prophylactic cervical cerclage in twin pregnancies even in cases with cervical shortening. Emergency cerclage remains an indication after individual counseling. The effect of a cervical pessary in singleton pregnancy seems to be more pronounced in studies where a few investigators with increasing experience have treated and followed the patients at risk for preterm birth. Mainly in twin pregnancies, pessary treatment seems to be promising compared to other treatment options of secondary prevention when the therapy is started at early stages of precocious cervical ripening. At present, several international trials with the goal to reduce global rates of prematurity are in progress which will hopefully allow to specify the indications and methods of intervention for certain subgroups. When trials are summarized, prospective meta-analyses carry a lower risk of bias than the meanwhile uncontrolled magnitude of retrospective meta-analyses with conflicting results.

Cervical pessaries for the prevention of preterm birth: a systematic review and meta-analysis

OBJECTIVE

The objective of this study is to evaluate the effectiveness and safety of cervical pessaries for the prevention of preterm birth.

METHODS

We searched PubMed, Embase, Web of Science, and other sources from inception to July 2016. This analysis referred to pregnant women with singleton/multiple viable fetus/fetuses, with or without cervical pessary placement.

RESULTS

Six randomized control trials and five cohort studies involving 3911 participants were included. Overall, cervical pessary placement was slightly associated with the decrease of spontaneous delivery less than 34 weeks (relative risk 0.65 [95% CI: 0.44-0.96]) and increased gestational age at delivery (weighted mean difference 1.03 weeks [95% CI: 0.37-1.70]) in multiple pregnancies, but not with poor perinatal outcomes. Pessary placement in singleton pregnancies did not show any difference. A planned subgroup analysis showed multiple pregnancies with shorter cervical length (≤25 mm) had a longer prolongation of pregnancy (weighted mean difference 2.08 weeks [95% CI: 1.35-2.82]).

CONCLUSION

This meta-analysis suggested pessary placement could slightly reduce the rate of spontaneous preterm delivery before 34 weeks, and increase gestational age at delivery in multiple pregnancies, but not in singleton pregnancies. More studies of high quality with detailed records are urgent to confirm the efficacy of this procedure.

Current options for mechanical prevention of preterm birth

Cervical insufficiency can be defined by a combination of obstetric history, cervical dilation on exam, and/or short cervical length in women with prior preterm birth. Options for mechanical intervention include cerclage and pessary. There is evidence to support the benefit of a cervical cerclage in women with singleton gestations who have a diagnosis of cervical insufficiency either based on second trimester painless cervical dilatation leading to recurrent early preterm births, or a history of early spontaneous preterm birth and a second trimester transvaginal ultrasound short cervical length or cervical dilation on exam. For women with multiple gestations, the benefit of a cerclage is uncertain, and further study is warranted. The pessary has also been studied for mechanical prevention of preterm birth in various populations, however the results so far have been mixed and warrants further study prior to routine use.

Do serial measurements of cervical length improve the prediction of preterm birth in asymptomatic women with twin gestations?

BACKGROUND

Cervical length at midtrimester is a powerful predictor of preterm birth in twin gestations. However, given the fact that, in some cases, cervical shortening may become evident only later during the second trimester, it seems reasonable that serial monitoring of cervical length may improve the detection of preterm birth in women with twins. However, data in support of such a practice are limited and conflicting. The contradictory results may be related to the fact that in most of these studies, the analysis of the predictive value of serial measurements of cervical length was limited to data derived from only two sequential measurements of cervical length, while data on the predictive value of multiple (>2) measurements are scarce.

OBJECTIVE

We sought to determine whether serial measurements of cervical length can improve the prediction of preterm birth in asymptomatic women with twin gestations compared with a single measurement of cervical length at midgestation.

STUDY DESIGN

This was a retrospective cohort study of women with twin pregnancies followed up in a tertiary medical center from 2012 through 2014. All participants underwent routine measurement of cervical length at midgestation and every 2-3 weeks thereafter until 28-32 weeks. For each patient, cervical length was determined at the following time periods: 18+0 to 21+6 weeks (period 1, routine exam), 22+0 to 24+6 weeks (period 2), 25+0 to 27+6 weeks (period 3), and 28+0 to 32+0 weeks (period 4). Measurements of cervical length at periods 2-4 were analyzed in the form of either absolute length (in millimeters) or percent shortening relative to cervical length at period 1. The performance of a stepwise algorithm that incorporated serial measurements of cervical length for the prediction of preterm birth was compared to that achieved with a single measurement of cervical length at period 1.

RESULTS

Overall, 441 women with twin pregnancies who were eligible for the study underwent a total of 2374 cervical length measurements. The association of a short cervix (<10th percentile) with preterm birth at <32 weeks persisted in each of the 4 periods of gestation [odds ratio (95% confidence interval): 7.2 (3.1-16.5), 15.3 (6.4-36.7), 10.3 (4.4-24.3), and 23.1(8.3-64.1), respectively]. Compared with a single measurement of cervical length at midgestation (period 1), a stepwise algorithm integrating serial cervical length measurements from all 4 successive gestational age periods resulted in a significant increase in the area under the receiver operating characteristic curve (0.917 vs 0.613, P < .001). Similarly, when a target false-positive rate of 5% was used, the same stepwise algorithm was associated with a higher detection rate (69% vs 28%, P < .001), higher positive likelihood ratio (14.54 vs 5.12), and lower negative likelihood ratio (0.32 vs 0.76) for preterm birth at <32 weeks compared with a single measurement of cervical length at period 1.

CONCLUSION

Integration of serial measurements of cervical length using a stepwise algorithm in asymptomatic women with twin gestations can improve the detection of women at risk of preterm birth. Prospective studies are needed to validate these findings, and to investigate whether improved risk assessment performance is sufficient to offset the additional costs associated with serial cervical length measurements.