Vaginal progesterone in women with an asymptomatic sonographic short cervix in the midtrimester decreases preterm delivery and neonatal morbidity: a systematic review and metaanalysis of individual patient data

Cerclage Plus Adjuvant Vaginal Progesterone for Preterm Birth Prevention in Patients with a Short or Dilated Cervix without Prior Preterm Birth

OBJECTIVE

 The primary objective was to determine if vaginal progesterone following cerclage for cervical length <10 mm or cervical dilation in patients without a history of spontaneous preterm birth (sPTB) decreased the risk of preterm birth at <34 weeks' gestation compared with cerclage alone. Secondary objectives were to determine if vaginal progesterone following cerclage (1) decreased the risk of preterm birth at <24, <28, and <37 weeks' gestation and (2) increased the latency period from cerclage placement to delivery compared with treatment with cerclage alone.

STUDY DESIGN

 Multicenter retrospective cohort study from 2015 to 2020 of singleton pregnancies, without prior sPTB, who had cerclage placement <24 weeks' gestation for cervical length <10 mm or cervical dilation. Exposure defined as cerclage plus vaginal progesterone postoperatively (dual therapy) and unexposed as cerclage alone (monotherapy), based on surgeon preference.

RESULTS

 We included 122 patients, 78 (64%) treated with dual therapy and 44 (36%) treated with monotherapy. In the crude analysis, dual therapy was associated with a lower risk of delivery at <28 weeks' gestation (13%) compared with monotherapy (34%; crude risk ratio: 0.38 [95% confidence interval (CI): 0.19-0.75]). When adjusted for preoperative vaginal progesterone, results were attenuated (adjusted risk ratio: 0.45 [95% CI: 0.20-1.01]). In both the crude and adjusted analyses, the risk of sPTB was not statistically different at <24, <34 or <37 weeks' gestation. Dual therapy was associated with a greater pregnancy latency from cerclage to delivery (16.3 vs. 14.4 weeks; p = 0.04), and greater gestational age at delivery (37.3 vs. 35.8 weeks' gestation; p = 0.02) compared with monotherapy.

CONCLUSION

 While not statistically significant, the risk of sPTB was lower at all gestational ages studied in patients treated with dual therapy compared with monotherapy. Dual therapy was associated with longer pregnancy latency and greater gestational age at delivery compared with monotherapy.

KEY POINTS

· Dual therapy did not decrease preterm birth risk compared with monotherapy.. · Dual therapy prolonged pregnancy compared with monotherapy.. · Dual therapy can be considered but further studies are needed..

The Effect of Maternal Parity on Preterm Birth Risk in Women with Short Mid-Trimester Cervical Length: A Retrospective Cohort Study

Objectives: To evaluate the effect of maternal parity on the association between mid-trimester cervical length and preterm birth to elucidate the potential intricacies of this relationship. Methods: A retrospective cohort study using Electronic Medical Records (EMR) data. The study population included pregnant women with a singleton fetus and a short mid-trimester cervical length, recorded in the EMR system at a large health maintenance organization. Women were categorized by parity in the current pregnancy, and a statistical analysis was conducted to examine the relationship between parity and premature delivery. Results: Data were collected from 1144 records of cervical length measurements of 738 pregnancies obtained from the HMO database. The study population consisted of 259 nulliparous women (35.1%), 451 multiparous women (61.1%), and 28 grand multiparous women (3.8%). The results from the multivariate analysis of the primary outcome showed that nulliparity was significantly associated with an increased risk of premature delivery, with a risk of 1.557 for nulliparous women compared to parous women. Conclusions: In this study, a statistically significant association was found between nulliparity and preterm birth among women with a short mid-trimester cervical length. Nulliparous women were found to have a higher risk of preterm birth in the current pregnancy compared to parous women. Further research is needed to understand the underlying mechanisms and to develop targeted interventions to reduce the risk of premature birth in this population. These findings highlight the need to consider nulliparity as a potential risk factor in the management of pregnancies with a shortened cervix.

SMFM Consult Series #70: Management of short cervix in individuals without a history of spontaneous preterm birth

Most deliveries before 34 weeks of gestation occur in individuals with no previous history of preterm birth. Midtrimester cervical length assessment using transvaginal ultrasound is one of the best clinical predictors of spontaneous preterm birth. This Consult provides guidance for the diagnosis and management of a short cervix in an individual without a history of preterm birth. The following are Society for Maternal-Fetal Medicine recommendations: (1) we recommend that all cervical length measurements used to guide therapeutic recommendations be performed using a transvaginal approach and in accordance with standardized procedures as described by organizations such as the Perinatal Quality Foundation or the Fetal Medicine Foundation (GRADE 1C); (2) we recommend using a midtrimester cervical length of ≤25 mm to diagnose a short cervix in individuals with a singleton gestation and no previous history of spontaneous preterm birth (GRADE 1C); (3) we recommend that asymptomatic individuals with a singleton gestation and a transvaginal cervical length of ≤20 mm diagnosed before 24 weeks of gestation be prescribed vaginal progesterone to reduce the risk of preterm birth (GRADE 1A); (4) we recommend that treatment with vaginal progesterone be considered at a cervical length of 21 to 25 mm based on shared decision-making (GRADE 1B); (5) we recommend that 17-alpha hydroxyprogesterone caproate, including compounded formulations, not be prescribed for the treatment of a short cervix (GRADE 1B); (6) in individuals without a history of preterm birth who have a sonographic short cervix (10-25 mm), we recommend against cerclage placement in the absence of cervical dilation (GRADE 1B); (7) we recommend that cervical pessary not be placed for the prevention of preterm birth in individuals with a singleton gestation and a short cervix (GRADE 1B); and (8) we recommend against routine use of progesterone, pessary, or cerclage for the treatment of cervical shortening in twin gestations outside the context of a clinical trial (GRADE 1B).

Vaginal Progesterone for Pregnancy Prolongation After Arrested Preterm Labor: A Randomized Clinical Trial

Importance

Women with arrested preterm labor (APTL) are at very high risk for spontaneous preterm delivery (SPTD), the leading cause of neonatal mortality and morbidity. To date, no maintenance therapy has been found to be effective for pregnancy prolongation. A few clinical trials with considerable methodological limitations have demonstrated some efficacy for 400 mg vaginal micronized progesterone (VMP) in women with APTL.

Objective

To investigate the effectiveness of daily 400 mg VMP for the prolongation of pregnancy after APTL.

Design, Setting, and Participants

This randomized clinical trial was conducted between December 19, 2018, and February 27, 2023, in 3 university-affiliated medical centers in Israel. Participants included women with singleton and twin pregnancies after APTL following tocolysis at 24 weeks 0 days to 34 weeks 0 days' gestation. Women with a history of preterm delivery or asymptomatic cervical shortening in the current pregnancy were excluded.

Interventions

Participants were randomly allocated to receive VMP 200 mg twice a day or no treatment until 36 weeks 6 days' gestation.

Main Outcomes and Measures

The primary end points were mean number of days from study enrollment to delivery and the rate of SPTD prior to 37 weeks' gestation.

Results

A total of 129 participants were enrolled (65 in the VMP group and 64 in the no-treatment group). Mean (SD) age was 27.6 (5.1) years. Between the VMP and no-treatment groups, there was no difference in pregnancy prolongation (mean [SD], 40.0 [17.8] vs 37.4 [20.3] days; P = .44) and the rate of SPTD (16 [25%] vs 19 [30%]; relative risk, 0.8; 95% CI, 0.5-1.5; P = .52). In twin pregnancies, including 12 and 15 pairs in the VMP and no-treatment groups, respectively, VMP prolonged pregnancy (mean [SD], 43.7 [18.1] vs 26.1 [15.2] days; P = .02), postponed the delivery week (36.5 [1.4] vs 34.7 [2.2] weeks; P = .01), shortened the length of stay in the neonatal intensive care unit (4.9 [10.6] vs 13.2 [18.5] days; P = .03) and overall hospital stay (8.3 [9.6] vs 15.1 [17.2] days; P = .03), and was associated with a higher birth weight (2444 [528] vs 2018 [430] g; P = .01).

Conclusions and Relevance

These findings show that VMP given in a dosage of 200 mg twice a day following APTL is not an effective treatment to prolong pregnancy or prevent SPTD. However, VMP demonstrated beneficial effects in twin pregnancies, warranting further investigation.

Trial Registration

ClinicalTrials.gov Identifier: NCT02430233.

Comparing cervical cerclage, pessary and vaginal progesterone for prevention of preterm birth in women with a short cervix (SuPPoRT): A multicentre randomised controlled trial

BACKGROUND

Cervical cerclage, cervical pessary, and vaginal progesterone have each been shown to reduce preterm birth (PTB) in high-risk women, but to our knowledge, there has been no randomised comparison of the 3 interventions. The SuPPoRT "Stitch, Pessary, or Progesterone Randomised Trial" was designed to compare the rate of PTB <37 weeks between each intervention in women who develop a short cervix in pregnancy.

METHODS AND FINDINGS

SuPPoRT was a multicentre, open label 3-arm randomised controlled trial designed to demonstrate equivalence (equivalence margin 20%) conducted from 1 July 2015 to 1 July 2021 in 19 obstetric units in the United Kingdom. Asymptomatic women with singleton pregnancies with transvaginal ultrasound cervical lengths measuring <25 mm between 14+0 and 23+6 weeks' gestation were eligible for randomisation (1:1:1) to receive either vaginal cervical cerclage (n = 128), cervical pessary (n = 126), or vaginal progesterone (n = 132). Minimisation variables were gestation at recruitment, body mass index (BMI), and risk factor for PTB. The primary outcome was PTB <37 weeks' gestation. Secondary outcomes included PTB <34 weeks', <30 weeks', and adverse perinatal outcome. Analysis was by intention to treat. A total of 386 pregnant women between 14+0 and 23+6 weeks' gestation with a cervical length <25 mm were randomised to one of the 3 interventions. Of these women, 67% were of white ethnicity, 18% black ethnicity, and 7.5% Asian ethnicity. Mean BMI was 25.6. Over 85% of women had prior risk factors for PTB; 39.1% had experienced a spontaneous PTB or midtrimester loss (>14 weeks gestation); and 45.8% had prior cervical surgery. Data from 381 women were available for outcome analysis. Using binary regression, randomised therapies (cerclage versus pessary versus vaginal progesterone) were found to have similar effects on the primary outcome PTB <37 weeks (39/127 versus 38/122 versus 32/132, p = 0.4, cerclage versus pessary risk difference (RD) -0.7% [-12.1 to 10.7], cerclage versus progesterone RD 6.2% [-5.0 to 17.0], and progesterone versus pessary RD -6.9% [-17.9 to 4.1]). Similarly, no difference was seen for PTB <34 and 30 weeks, nor adverse perinatal outcome. There were some differences in the mild side effect profile between interventions (vaginal discharge and bleeding) and women randomised to progesterone reported more severe abdominal pain. A small proportion of women did not receive the intervention as per protocol; however, per-protocol and as-treated analyses showed similar results. The main study limitation was that the trial was underpowered for neonatal outcomes and was stopped early due to the COVID-19 pandemic.

CONCLUSIONS

In this study, we found that for women who develop a short cervix, cerclage, pessary, and vaginal progesterone were equally efficacious at preventing PTB, as judged with a 20% equivalence margin. Commencing with any of the therapies would be reasonable clinical management. These results can be used as a counselling tool for clinicians when managing women with a short cervix.

TRIAL REGISTRATION

EU Clinical Trials register. EudraCT Number: 2015-000456-15, clinicaltrialsregister.eu., ISRCTN Registry: ISRCTN13364447, isrctn.com.

Cervical length measurement between 11 and 13 + 6 weeks of pregnancy: Comparison of maternal and ultrasonographic characteristics between term and preterm deliveries

OBJECTIVE

The aim of this study was to evaluate the maternal and ultrasonographic characteristics of pregnant women who underwent cervical length (CL) measurement by transvaginal ultrasound between 11 and 13 + 6 weeks of gestation and who delivered at term or preterm.

METHODS

A retrospective cohort study was carried out between March 2013 and December 2018 by analyzing ultrasound data of singleton pregnant women who underwent CL measurement by transvaginal ultrasound during the first trimester scan. CL was compared between the two groups (full-term and preterm birth [PB]) using Student's t-test.

RESULTS

A total of 5097 pregnant women were enrolled, of whom 5061 (99.3%) had term and 36 (0.7%) had PB < 34 weeks. CL measurements did not differ between the term and preterm groups (36.62 vs. 37.83 mm, p = 0.08). Maternal age showed a significant and linear association with CL (r = 0.034, p = 0.012) and CRL (r = 0.086, p < 0.001). Smoking status was associated with shorter CL (36.64 vs. 35.09 mm, p = 0.003). When we analyzed the CL of the pregnant women in the term and preterm groups, according to the gestational age cut-offs for prematurity (28, 30, 32, and 34 weeks), we found that there was no significant difference between the measurements in all groups (p > 0.05).

CONCLUSION

We observed no significant differences between CL measurements between 11 and 13 + 6 weeks in pregnant women who had preterm and term deliveries. Gestational age and CRL showed a significant and linear association with CL measurement.

Vaginal Progesterone to Prevent Spontaneous Preterm Birth in Women With a Sonographic Short Cervix: The Story of the PREGNANT Trial

The PREGNANT trial was a randomized, placebo-controlled, multicenter trial designed to determine the efficacy and safety of vaginal progesterone (VP) to reduce the risk of birth < 33 weeks and of neonatal complications in women with a sonographic short cervix (10 to 20 mm) in the mid-trimester (19 to 23 6/7 wk). Patients allocated to receive VP had a 45% lower rate of preterm birth (8.9% vs 16.1%; relative risk = 0.55; 95% CI: 0.33-0.92). Neonates born to mothers allocated to VP had a 60% reduction in the rate of respiratory distress syndrome. This article reviews the background, design, execution, interpretation, and impact of the PREGNANT Trial.

PROMPT: Prospective Meta-analysis for Pessary Trials Study Protocol

OBJECTIVE

Preterm birth, defined as birth before 37 weeks of gestation, is a leading cause of perinatal and infant mortality throughout the world. Preterm birth is also associated with long-term neurological disabilities and other significant health issues in children. A short cervix in the second trimester has been noted to be one of the strongest predictors of subsequent spontaneous preterm birth in both singleton and multiple pregnancies. Some studies have shown that cervical support in the form of an Arabin pessary lowers the risk of preterm birth in women with a singleton gestation and short cervical length; however, other studies have conflicting results. Our objective was to form an international collaborative of planned or ongoing randomized trials of pessary in singleton and twin gestations with a short cervix.

STUDY DESIGN

In November 2014, an international group of investigators, who had initiated or were planning randomized trials of pessary for pregnant people with a short cervix and singleton or twin gestation to prevent preterm birth, formed a collaboration to plan a prospective individual patient data (IPD) meta-analysis of randomized trials (PROspective Meta-analysis of Pessary Trials [PROMPT]). The PROMPT investigators agreed on meta-analysis IPD hypotheses for singletons and twins, eligibility criteria, and a set of core baseline and outcome measures. The primary outcome is a composite of fetal death or preterm delivery before 32 weeks' gestation. Secondary outcomes include maternal and neonatal morbidities. The PROMPT protocol may be viewed as a written agreement among the study investigators who make up the PROMPT consortium (PROSPERO ID# CRD42018067740).

RESULTS

Results will be published in phases as the individual participating studies are concluded and published. Results of the first phase of singleton and twin pessary trials are expected to be available in late 2022. Updates are planned as participating trials are completed and published.

KEY POINTS

· Short cervical length predicts preterm birth.. · Results of prior cervical pessary trials are mixed.. · Meta-analysis of pessary trials protocol..

The effect of cervical pessary on increasing gestational age at delivery in twin pregnancies with asymptomatic short cervix: a systematic review and meta-analysis of randomized controlled trials

Objective

The incidence of preterm delivery is much higher in twin pregnancies than in singletons and even higher if a short cervical length is detected in the second trimester. Studies are contradictory regarding the efficacy of a cervical pessary to decrease preterm birth in twin pregnancies and short cervical length. To conduct a systematic review and meta-analysis investigating the efficacy of cervical pessary in prolonging gestation, preventing preterm birth, and reducing adverse neonatal outcomes in twin pregnancies with an asymptomatic short cervix.

Data sources

PubMed, Scopus, Web of Science, and ClinicalTrials.org were searched for randomized controlled trials from inception to June 2023.

Study eligibility criteria

In this study, randomized controlled trials comparing the cervical pessary to expectant management in the pregnant population with twin gestations and asymptomatic short cervix were included.

Methods

The Cochrane risk-of-bias-2 tool for randomized controlled trials was used for the evaluation of the risk of bias in included studies. A meta-analysis was performed by calculating risk ratio and mean difference with their 95% confidence interval using the random effects model or fixed effect model on the basis of heterogeneity and accounting for potential covariates among the included randomized controlled trials.

Results

A total of 6 randomized controlled trials were included in the analysis. Cervical pessary did not significantly increase the gestational age at delivery in twin pregnancies with asymptomatic patients (mean difference, 0.36 weeks [-0.27 to 0.99]; P=.270; I2=72.0%). Moreover, the cervical pessary use did not result in a reduction of spontaneous or all-preterm birth before 37 weeks of gestation (risk ratio, 0.88 [0.77-1.00]; P=.061; I2=0.0%). There was no statistically significant difference in the composite neonatal adverse outcomes (risk ratio, 1.001 [0.86-1.16]; P=.981; I2=20.9%), including early respiratory morbidity, intraventricular hemorrhage, necrotizing enterocolitis, and confirmed sepsis.

Conclusion

The use of cervical pessary in twin pregnancies with asymptomatic short cervix does not seem to be effective in increasing the gestational age at delivery, preventing preterm birth, or reducing adverse neonatal outcomes. This indicates that alternative interventions should be sought for the management of this patient population.

Pregnant Populations which Benefit from Vaginal Progesterone for Preventing Preterm Birth at <34 Weeks and Neonatal Morbidities: A Systematic Review and Meta-analysis

This study aimed to assess vaginal progesterone's effect on different populations and performed comparation between women with varied risk factors. Embase, PubMed, Cochrane library (CENTRAL) were searched without restriction to language up to February 25, 2021. Randomized controlled trials (RCTs) assessing vaginal progesterone administered to women at risk of preterm birth at <37 weeks. Two reviewers independently extracted data, and pooled relative risk (RR) with 95% confidence intervals (CIs) was calculated as well. Women with short cervix have a significantly lower risk of preterm birth at <34 weeks (pooled RR = 0.65; 95% CI: 0.55-0.77; I 2 = 0; p < 0.001; nine studies) and some neonatal morbidities; interaction tests showed that effect of vaginal progesterone differs significantly between women with short cervix and those with other risk factors (history of preterm birth, exclusive twin gestation, and vaginal bleeding). Evidences of this study showed that singleton gestations, as well as women with short cervix, benefit from vaginal progesterone in preventing preterm birth at <34 weeks and some neonatal morbidities. Women with short cervix are populations who benefit the most among other risk populations. KEY POINTS: · Vaginal progesterone reduces preterm birth and neonatal morbidities.. · Vaginal progesterone effects on some specific populations.. · Women with short cervix benefit the most..

A pragmatic evaluation of the implementation and acceptance of a universal second trimester cervical length screening program in an un-selected population

PURPOSE

To evaluate patients' acceptance of a universal transvaginal ultrasound cervical length (CL) screening program and the feasibility of initiating treatment with progesterone in a clinical setting in women found to have a short cervix.

METHODS

An observational, pragmatic cohort study was conducted at one tertiary care facility from 2012-2015, involving eligible women with singleton pregnancies who accepted and underwent second-trimester CL screening. The primary outcomes were the percentage of women who were eligible and accepting of screening, compliance with progesterone treatment, and the screening value of TVCL in predicting SPTB. Secondary outcomes were the number of women who received progesterone treatment and the rates of SPTB.

RESULTS

Overall cervical length screening acceptance rate was found to be 82.5%. Of the 797 women that underwent screening, 21 women (2.6%) had a TVCL < 25 mm, of whom nine had a TVCL < 20.0 mm. Nineteen of the 21 women with a TVCL < 25 mm were treated with progesterone, with a 94.7% compliance rate. Delivery outcomes were obtained for 767 women. Of those with a TVCL < 25 mm, there was a 35% rate of SPTB as opposed to a 6.3% SPTB rate in those with TVCL > 25 mm. The negative predictive value for SPTB with a TVCL 25 mm or greater was 94.0%.

CONCLUSION

Universal cervical length screening was successfully implemented in 82.5% of the patient population with a high compliance rate with progesterone treatment. Furthermore, there was a higher rate of SPTB in those with a shorter cervix. Based on our outcomes obtained in an observational and pragmatic manner, we showed that incorporating second trimester transvaginal cervical length screening into routine clinical practice is readily accepted and, with the addition of vaginal progesterone treatment, may reduce the rate of prematurity.

Addressing a broken drug pipeline for preterm birth: why early preterm birth is an orphan disease

Preterm birth remains one of the most urgent unresolved medical problems in obstetrics, yet only 2 therapeutics for preventing preterm birth have ever been approved by the United States Food and Drug Administration, and neither remains on the market. The recent withdrawal of 17-hydroxyprogesterone caproate (17-OHPC, Makena) marks a new but familiar era for obstetrics with no Food and Drug Administration-approved pharmaceuticals to address preterm birth. The lack of pharmaceuticals reflects a broad and ineffective pipeline hindered by extensive regulatory hurdles, soaring costs of performing drug research, and concerns regarding adverse effects among a particularly vulnerable population. The pharmaceutical industry has historically limited investments in research for diseases with similarly small markets, such as cystic fibrosis, given their rarity and diminished projected financial return. The Orphan Drug Act, however, incentivizes drug development for "orphan diseases", defined as affecting <200,000 people in the United States annually. Although the total number of preterm births in the United States exceeds this threshold annually, the early subset of preterm birth (<34 weeks' gestation) would qualify, which is predominantly caused by inflammation and infection. The scientific rationale for classifying preterm birth into early and late subsets is strong given that their etiologies differ, and therapeutics that may be efficacious for one subset may not work for the other. For example, antiinflammatory therapeutics would be expected to be highly effective for early but not late preterm birth. A robust therapeutic pipeline of antiinflammatory drugs already exists, which could be used to target spontaneous early preterm birth, in combination with antibiotics shown to sterilize the amniotic cavity. New applications for therapeutics targeting spontaneous early preterm birth could categorize as orphan disease drugs, which could revitalize the preterm birth therapeutic pipeline. Herein, we describe why drugs targeting early preterm birth should qualify for orphan status, which may increase pharmaceutical interest for this vitally important obstetrical condition.

Risk of pre-term birth as a function of sleep quality and obesity: prospective analysis in a large Prematurity Research Cohort

Study Objective

To investigate whether poor sleep quality is associated with pre-term birth (PTB) risk, overall and independent of sleep apnea and habitual snoring.

Methods

We used longitudinal data from the Washington University Prematurity Research Cohort to investigate the association between poor sleep quality (defined as a Pittsburgh Sleep Quality Index > 5) and PTB, overall and independent of sleep apnea and snoring (defined by the Berlin questionnaire and prior sleep clinic attendance). Associations were investigated for sleep quality early and throughout pregnancy. Stratified analyses were performed by factors previously shown to modify associations between sleep and PTB (race, pre-pregnancy obesity).

Results

Of the 976 eligible participants, 50.1% experienced poor sleep quality early in pregnancy (<20 completed weeks) and 14.2% delivered pre-term (n = 50 without and 89 with poor sleep quality). In multivariable-adjusted analyses, poor sleep quality early in pregnancy was associated with increased PTB risk (hazard ratio [HR] = 1.48, 95% confidence interval [CI] = 1.02-2.14). This association persisted after further adjustment for sleep apnea and snoring (HR = 1.50, 95% CI = 1.02-2.20) and in analyses stratified by race. It varied, however, by pre-pregnancy obesity. Among individuals without obesity, no association was observed between poor sleep and PTB (HR = 1.08, 95% CI = 0.65-1.79), whereas among those with obesity, a positive association was observed (HR = 2.94, 95% CI = 1.52-5.69, p-interaction = .05). This association was limited to individuals with obesity who experienced poor sleep both earlier and later in pregnancy (HR = 3.94, 95% CI = 1.56-9.99).

Conclusion

Our findings suggest that improving sleep quality early in pregnancy may be important for PTB prevention, particularly among individuals with obesity.

Progesterone control of myometrial contractility

During pregnancy, the primary function of the uterus is to be quiescent and not contract, which allows the growing fetus to develop and mature. A uterine muscle layer, myometrium, is composed of smooth muscle cells (SMCs). Before the onset of labor contractions, the uterine SMCs experience a complex biochemical and molecular transformation involving the expression of contraction-associated proteins. Labor is initiated when genes in SMCs are activated in response to a combination of hormonal, inflammatory and mechanical signals. In this review, we provide an overview of molecular mechanisms regulating the process of parturition in humans, focusing on the hormonal control of the myometrium, particularly the steroid hormone progesterone. The primary reason for discussing the regulation of myometrial contractility by progesterone is the importance of the clinical problem of preterm birth. It is thought that the hormonal mechanisms regulating premature uterine contractions represent an untimely triggering of the normal events occurring during term parturition. Yet, our knowledge of the complex and redundant hormonal pathways controlling uterine contractile activity leading to delivery of the neonate remains incomplete. Finally, we introduce recent animal studies using a novel class of drugs, Selective Progesterone Receptor Modulators, targeting progesterone signaling to prevent premature myometrial contractions.

Progestogen maintenance therapy for prolongation of pregnancy after an episode of preterm labour: A systematic review and meta-analysis

BACKGROUND

Evidence for progestogen maintenance therapy after an episode of preterm labour (PTL) is contradictory.

OBJECTIVES

To assess effectiveness of progestogen maintenance therapy after an episode of PTL.

SEARCH STRATEGY

An electronic search in Central Cochrane, Ovid Embase, Ovid Medline and clinical trial databases was performed.

SELECTION CRITERIA

Randomised controlled trials (RCT) investigating women between 16+0 and 37+0  weeks of gestation with an episode of PTL who were treated with progestogen maintenance therapy compared with a control group.

DATA COLLECTION AND ANALYSIS

Systematic review and meta-analysis were conducted. The primary outcome was latency time in days. Secondary neonatal and maternal outcomes are consistent with the core outcome set for preterm birth studies. Studies were extensively assessed for data trustworthiness (integrity) and risk of bias.

MAIN RESULTS

Thirteen RCT (1722 women) were included. Progestogen maintenance therapy demonstrated a longer latency time of 4.32 days compared with controls (mean difference [MD] 4.32, 95% CI 0.40-8.24) and neonates were born with a higher birthweight (MD 124.25 g, 95% CI 8.99-239.51). No differences were found for other perinatal outcomes. However, when analysing studies with low risk of bias only (five RCT, 591 women), a significantly longer latency time could not be shown (MD 2.44 days; 95% CI -4.55 to 9.42).

CONCLUSIONS

Progestogen maintenance therapy after PTL might have a modest effect on prolongation of latency time. When analysing low risk of bias studies only, this effect was not demonstrated. Validation through further research, preferably by an individual patient data meta-analysis is highly recommended.

Development and validation of a nomogram to predict spontaneous preterm birth in singleton gestation with short cervix and no history of spontaneous preterm birth

Background

Spontaneous preterm birth (sPTB) stands as a leading cause of neonatal mortality. Consequently, preventing sPTB has emerged as a paramount concern in healthcare. Therefore, our study aimed to develop a nomogram, encompassing patient characteristics and cervical elastography, to predict sPTB in singleton pregnancies. Specifically, we targeted those with a short cervix length (CL), no history of sPTB, and who were receiving vaginal progesterone therapy.

Methods

A total of 568 patients were included in this study. Data from 392 patients, collected between January 2016 and October 2019, constituted the training cohort. Meanwhile, records from 176 patients, spanning November 2019 to January 2022, formed the validation cohort. Following the univariate logistic regression analysis, variables exhibiting a P-value less than 0.05 were integrated into a multivariable logistic regression analysis. The primary objective of this subsequent analysis was to identify the independent predictors linked to sPTB in the training cohort. Next, we formulated a nomogram utilizing the identified independent predictors. This tool was designed to estimate the likelihood of sPTB in singleton pregnancies, particularly those with a short CL, devoid of any sPTB history, and undergoing vaginal progesterone therapy. The C-index, Hosmer-Lemeshow (HL) test, calibration curves, decision curve analysis (DCA), and receiver operating characteristic (ROC) were used to validate the performance of the nomogram.

Results

Upon finalizing the univariate analysis, we progressed to a multivariable analysis, integrating 8 variables with P < 0.05 from the univariate analysis. The multivariable analysis identified 7 independent risk factors: maternal age (OR = 1.072; P < 0.001), cervical length (OR = 0.854; P < 0.001), uterine curettage (OR = 7.208; P < 0.001), GDM (OR = 3.570; P = 0.006), HDP (OR = 4.661; P = 0.003), C-reactive protein (OR = 1.138; P < 0.001), and strain of AI (OR = 7.985; P < 0.001). The nomogram, tailored for sPTB prediction, was grounded on these 7 independent predictors. In predicting sPTB, the C-indices manifested as 0.873 (95% CI, 0.827-0.918) for the training cohort and 0.916 (95%CI, 0.870-0.962) for the validation cohorts, underscoring a good discrimination of the model. Additionally, the ROC curves served to evaluate the discrimination of nomogram model across both cohorts. Calibration curves were delineated, revealing no statistically significant differences in both the training (χ2 = 5.355; P = 0.719) and validation (χ2 = 2.708; P = 0.951) cohorts as evidenced by the HL tests. Furthermore, the DCA underscored the model's excellence as a predictive tool for sPTB.

Conclusions

By amalgamating patient characteristics and cervical elastography data from the second trimester, the nomogram emerged as a visually intuitive and dependable tool for predicting sPTB. Its relevance was particularly pronounced for singleton pregnancies characterized by a short CL, an absence of prior sPTB incidents, and those receiving vaginal progesterone therapy.

Bioengineering and the cervix: The past, current, and future for addressing preterm birth

The uterine cervix plays two important but opposing roles during pregnancy - as a mechanical barrier that maintains the fetus for nine months and as a compliant structure that dilates to allow for the delivery of a baby. In some pregnancies, however, the cervix softens and dilates prematurely, leading to preterm birth. Bioengineers have addressed and continue to address the lack of reduction in preterm birth rates by developing novel technologies to diagnose, prevent, and understand premature cervical remodeling. This article highlights these existing and emerging technologies and concludes with open areas of research related to the cervix and preterm birth that bioengineers are currently well-positioned to address.

Reassessing Preterm Birth Prevention After the Withdrawal of 17-α Hydroxyprogesterone Caproate

The U.S. Food and Drug Administration has recently withdrawn approval for 17-α hydroxyprogesterone caproate for prevention of recurrent preterm birth, and recent studies have called into question benefits of the pessary in the setting of a short cervix. Obstetric health care professionals are once again left with limited remaining options for preterm birth prevention. This narrative review summarizes the best current evidence on the use of vaginal progesterone, low-dose aspirin, and cerclage for the prevention of preterm birth; attempts to distill possible lessons learned from studies of progesterone and pessary, as well as their implementation into practice; and highlights areas where inroads into preterm birth prevention may be possible outside of the progesterone-aspirin-cerclage paradigm.

Cervical Cerclage: A Comprehensive Review of Major Guidelines

Importance

Cervical cerclage (CC) represents one of the few effective measures currently available for the prevention of preterm delivery caused by cervical insufficiency, thus contributing in the reduction of neonatal morbidity and mortality rates.

Objective

The aim of this study was to review and compare the most recently published major guidelines on the indications, contraindications, techniques, and timing of placing and removal of CC.

Evidence Acquisition

A descriptive review of guidelines from the American College of Obstetricians and Gynecologists (ACOG), the Royal College of Obstetricians and Gynaecologists (RCOG), the Society of Obstetricians and Gynaecologists of Canada (SOGC), and the International Federation of Gynecology and Obstetrics (FIGO) on CC was carried out.

Results

There is a consensus among the reviewed guidelines regarding the recommended techniques, the indications for rescue CC, the contraindications, as well as the optimal timing of CC placement and removal. All medical societies also agree that ultrasound-indicated CC is justified in women with history of prior spontaneous PTD or mid-trimester miscarriage and a short cervical length detected on ultrasound. In addition, after CC, serial sonographic measurement of the cervical length, bed rest, and routine use of antibiotics, tocolysis, and progesterone are unanimously discouraged. In case of established preterm labor, CC should be removed, according to ACOG, RCOG, and SOGC. Furthermore, RCOG and SOGC agree on the prerequisites that should be met before attempting CC. These 2 guidelines along with FIGO recommend history-indicated CC for women with 3 or more previous preterm deliveries and/or second trimester pregnancy miscarriages, whereas the ACOG suggests the use of CC in singleton pregnancies with 1 or more previous second trimester miscarriages related to painless cervical dilation or prior CC due to painless cervical dilation in the second trimester. The role of amniocentesis in ruling out intra-amniotic infection before rescue CC remains a matter of debate.

Conclusions

Cervical cerclage is an obstetric intervention used to prevent miscarriage and preterm delivery in women considered as high-risk for these common pregnancy complications. The development of universal international practice protocols for the placement of CC seems of paramount importance and will hopefully improve the outcomes of such pregnancies.

A new care pathway to optimize gestational weight gain in twin pregnancies

BACKGROUND

Maternal gestational weight gain is an important determinant of pregnancy outcomes and may have an even greater role in twin pregnancies because of their higher rate of pregnancy complications and greater nutritional demands. However, data on the optimal week-specific gestational weight gain in twin pregnancies and on interventions that should be applied in cases of inadequate gestational weight gain are limited.

OBJECTIVE

This study aimed to determine whether a new care pathway that involves monitoring gestational weight gain using a week-specific chart, along with a standardized protocol for managing cases with inadequate gestational weight gain, can optimize maternal gestational weight gain in twin pregnancies.

METHODS

In this study, patients with twin pregnancies followed in a single tertiary center between February 2021 and May 2022 were exposed to the new care pathway (postintervention group). Gestational weight gain and clinical outcomes were compared with those of a previously described cohort of patients with twins followed in our clinic before the implementation of the new care pathway (preintervention group). The new care pathway targeted patients and care providers and included educational material, a newly developed body mass index group-specific gestational weight gain chart, and a stepwise management algorithm in cases of inadequate gestational weight gain. The body mass index group-specific gestational weight gain charts were divided into 3 zones: (1) green zone (optimal gestational weight gain at 25th-75th centiles); (2) yellow zone (suboptimal gestational weight gain at 5th-24th or 76th-95th centiles); and (3) gray zone (abnormal gestational weight gain, at <5th or >95th centile). The primary outcome was the overall proportion of patients achieving optimal gestational weight gain at birth.

RESULTS

A total of 123 patients were exposed to the new care pathway and were compared with 1079 patients from the preintervention period. Patients in the postintervention group were more likely to achieve optimal gestational weight gain at birth (60.2% vs 47.7%; adjusted odds ratio, 1.91; 95% confidence interval, 1.28-2.86) and were less likely to achieve low-suboptimal gestational weight gain (7.3% vs 14.7%; adjusted odds ratio, 0.41; 95% confidence interval, 0.20-0.85) or any suboptimal gestational weight gain (26.8% vs 34.8%; adjusted odds ratio, 0.60; 95% confidence interval, 0.39-0.93) at birth. In addition, patients in the postintervention group were less likely to have low-abnormal gestational weight gain anytime during gestation (18.9% vs 29.1%; P=.017) and were more likely to have normal gestational weight gain throughout pregnancy (21.3% vs 14.0%; P=.031) or high-abnormal gestational weight gain anytime during gestation (18.0% vs 11.1%; P=.025), suggesting that in comparison with standard care, the new care pathway is more effective in preventing patients from moving into the low-abnormal zone than the high-abnormal zone. Furthermore, the new care pathway was more effective than standard care in correcting high-suboptimal gestational weight gain and high-abnormal gestational weight gain.

CONCLUSION

Our findings suggest that the new care pathway may be effective in optimizing maternal gestational weight gain in twin gestations, which may in turn contribute to better clinical outcomes. This is a simple, low-cost intervention that can be easily disseminated among providers caring for patients with twin pregnancies.

Comparing the efficacy of vaginal micronized progesterone gel and capsule for prevention of preterm birth in singleton pregnancies with short cervical length at midtrimester: an indirect comparison meta-analysis

Objective: To evaluate the effectiveness of vaginal progesterone in preventing preterm birth in women with a singleton gestation and short cervical length and to determine which of the two formulations, micronized progesterone vaginal capsule versus vaginal gel containing micronized progesterone, is more effective for preventing preterm birth. Data sources: A systematic search was performed in the following databases: EMBASE, PubMed (MEDLINE), The Cochrane Library, and the Clinical Trials Registry (clinicaltrials.gov). Study eligibility criteria: Randomized controlled trials (RCTs), prospective and retrospective observational studies were included. We searched for progesterone administration to prevent preterm birth in asymptomatic women with a shortened cervix (<25 mm) measured by ultrasound in the second trimester of singleton pregnancy. Study appraisal and synthesis methods: Assessments of the risk of bias of RCTs were performed by applying the Cochrane Collaboration's Risk of Bias Tool; non-randomized control trials were evaluated with the Newcastle-Ottawa Scale (NOS). The primary outcome was preterm birth ≤33 weeks of gestation. Pooled relative risks (RR) and 95% CI's were calculated for dichotomous outcomes. Heterogeneity of treatment effect was assessed with the I² statistic. We pooled results of the primary outcome for individual studies using a random-effect model. We then performed a network meta-analysis to pool indirect comparisons between the two formulations (gel vs capsule). This analysis was performed using the network meta-analysis package within the R environment. Results: Five studies met the inclusion criteria (4 RCTs, one cohort study) including 1,048 women. The meta-analysis demonstrated that vaginal micronized progesterone significantly reduces preterm birth risk, Risk Ratio = 0.63; 95% CI, 0.48-0.82; p = 0.0006; with no heterogeneity between the studies: I ² = 0%. In the network meta-analysis, no significant difference was demonstrated (OR = 0.85; 95% CI, 0.43-1.69) between the effect of the two formulations of vaginal micronized progesterone (vaginal gel versus vaginal capsules) on the risk of PTB. Conclusion: Vaginal progesterone is associated with a decreased risk of premature birth in women with a shortened cervix in the second trimester of pregnancy. No differences were found between vaginal micronized progesterone in gel or capsule formulations. Systematic Review Registration: PROSPERO, identifier CRD42020165198.

Declining incidence of cerebral palsy in South Korea

Presuming that the incidence of cerebral palsy (CP) in Korea is decreasing due to medical advances, we analyzed the trends and risk factors of CP in changing circumstances. We identified all women who delivered a singleton between 2007 and 2015 using the Korea National Health Insurance (KNHI). Information on pregnancy and birth was obtained by linking the KNHI claims database and data from the national health-screening program for infants and children. The 4-years incidence of CP decreased significantly from 4.77 to 2.52 per 1000 babies during the study period. The multivariate analysis revealed that the risk of developing CP was 29.5 times higher in preterm infants born before 28 weeks of gestational age, 24.5 times higher in infants born between 28 and 34 weeks, and 4.5 times higher in infants born between 34 and 36 weeks, compared to full-term appropriate for age (2.5 ~ 4 kg of body weight) infants. 5.6 times higher in those with birth weight < 2500 g, and 3.8 times higher in pregnancies with polyhydramnios. Additionally, respiratory distress syndrome increased the risk of developing CP by 2.04 times, while necrotizing enterocolitis was associated with a 2.80-fold increased risk of CP. In Korea, the incidence of CP in singleton decreased from 2007 to 2015. We need to continue to focus on developing medical technologies for the early detection of high-risk neonates and minimizing brain damage to reduce the incidence rate of CP effectively.

Maternal Infection and Preterm Birth: From Molecular Basis to Clinical Implications

As the leading cause of neonatal morbidity and mortality, preterm birth is recognized as a major public health concern around the world. The purpose of this review is to analyze the connection between infections and premature birth. Spontaneous preterm birth is commonly associated with intrauterine infection/inflammation. The overproduction of prostaglandins caused by the inflammation associated with an infection could lead to uterine contractions, contributing to preterm delivery. Many pathogens, particularly Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Gardnerella vaginalis, Ureaplasma urealyticum, Mycoplasma hominis, Actinomyces, Candida spp., and Streptococcus spp. have been related with premature delivery, chorioamnionitis, and sepsis of the neonate. Further research regarding the prevention of preterm delivery is required in order to develop effective preventive methods with the aim of reducing neonatal morbidity.

Investigation and Management of Recurrent Pregnancy Loss: A Comprehensive Review of Guidelines

Importance

Recurrent pregnancy loss (RPL) is one of the most frustrating clinical entities in reproductive medicine requiring not only diagnostic investigation and therapeutic intervention, but also evaluation of the risk for recurrence.

Objective

The aim of this study was to review and compare the most recently published major guidelines on investigation and management of RPL.

Evidence Acquisition

A descriptive review of guidelines from the Royal College of Obstetricians and Gynaecologists, the European Society of Human Reproduction and Embryology, the American Society for Reproductive Medicine, the French College of Gynecologists and Obstetricians, and the German, Austrian, and Swiss Society of Gynecology and Obstetrics on RPL was carried out.

Results

There is consensus among the reviewed guidelines that the mainstays of RPL investigation are a detailed personal history and screening for antiphospholipid syndrome and anatomical abnormalities of the uterus. In contrast, inherited thrombophilias, vaginal infections, and immunological and male factors of infertility are not recommended as part of a routine RPL investigation. Several differences exist regarding the necessity of the cytogenetic analysis of the products of conception, parental peripheral blood karyotyping, ovarian reserve testing, screening for thyroid disorders, diabetes or hyperhomocysteinemia, measurement of prolactin levels, and performing endometrial biopsy. Regarding the management of RPL, low-dose aspirin plus heparin is indicated for the treatment of antiphospholipid syndrome and levothyroxine for overt hypothyroidism. Genetic counseling is required in case of abnormal parental karyotype. The Royal College of Obstetricians and Gynaecologists, the European Society of Human Reproduction and Embryology, and the French College of Gynecologists and Obstetricians guidelines provide recommendations that are similar on the management of cervical insufficiency based on the previous reproductive history. However, there is no common pathway regarding the management of subclinical hypothyroidism and the surgical repair of congenital and acquired uterine anomalies. Use of heparin for inherited thrombophilias and immunotherapy and anticoagulants for unexplained RPL are not recommended, although progesterone supplementation is suggested by the American Society for Reproductive Medicine and the German, Austrian, and Swiss Society of Gynecology and Obstetrics.

Conclusions

Recurrent pregnancy loss is a devastating condition for couples. Thus, it seems of paramount importance to develop consistent international practice protocols for cost-effective investigation and management of this early pregnancy complication, with the aim to improve live birth rates.

The effects of progesterone on immune cellular function at the maternal-fetal interface and in maternal circulation

Progesterone is a sex steroid hormone that plays a critical role in the establishment and maintenance of pregnancy. This hormone drives numerous maternal physiological adaptations to ensure the continuation of pregnancy and to facilitate fetal growth, including broad and potent modulation of the maternal immune system to promote maternal-fetal tolerance. In this brief review, we provide an overview of the immunomodulatory functions of progesterone in the decidua, placenta, myometrium, and maternal circulation during pregnancy. Specifically, we summarize current evidence of the regulated functions of innate and adaptive immune cells induced by progesterone and its downstream effector molecules in these compartments, including observations in human pregnancy and in animal models. Our review highlights the gaps in knowledge of interactions between progesterone and maternal cellular immunity that may direct future research.

Is mid-trimester cervical length screening effective for reduction of threatened preterm labor?

OBJECTIVE

To assess the incidence of threatened preterm labor and preterm labor admissions and treatment of women with singleton gestations and no prior preterm birth before and after implementation of the universal mid-trimester transvaginal ultrasound cervical length screening.

MATERIALS AND METHODS

A retrospective cohort study included of singleton gestations without a history of preterm birth presenting with threatened preterm labor between 24 0/7 and 36 6/7 gestational week in two study periods: before and after the implementation of the universal cervical length screening. Women with cervical length <25 mm were considered being at high risk for preterm birth and were prescribed a treatment with vaginal progesterone daily. The primary outcome was the incidence of threatened preterm labor. Secondary outcomes were the incidence of preterm labor.

RESULTS

We have found a significant increase in the incidence of threatened preterm labor from 6.42% (410/6378) in 2011 to 11.61% (483/4158) in 2018 (p < 0.0001). Gestational age at triage consult was lower in than in 2011, although the rate of admission for threatened preterm labor was similar in both periods. There was a significant decrease in the incidence of preterm delivery <37 weeks from 25.60% in 2011 to 15.94% in 2018 (p < 0.0004). Although there was a reduction in preterm delivery ≤34 weeks, this reduction was not significant.

CONCLUSION

The universal mid-trimester cervical length screening in asymptomatic women is not associated with a reduction in the frequency of threatened preterm labor or the admission rate for preterm labor, but reduces the rate of preterm births.

The clinical utility of ongoing sonographic cervix length surveillance in pregnancies prescribed vaginal progesterone therapy

BACKGROUND

Vaginal progesterone therapy significantly reduces preterm birth (PTB) rates in those high-risk pregnancies with a sonographic short cervix (≤25 mm) and/or a history of spontaneous PTB. Cervical length (CL) is routinely measured at the midtrimester morphology scan; however, CL surveillance thereafter is not currently recommended. Progesterone's precise mechanism of action remains unknown, though if it indeed influences CL, shortening after treatment initiation could indicate therapeutic failure and risk of PTB.

AIMS

The aim was to explore the utility of serial transvaginal ultrasound (TVU) measurement of CL at 16, 19 and 22 weeks for predicting PTB in high-risk pregnancies prescribed progesterone therapy.

METHODS

A retrospective cohort study was conducted involving women who attended the King Edward Memorial Hospital PTB Prevention Clinic from 2015 to 2019 and were prescribed progesterone therapy. CL was measured at 16, 19 and 22 weeks by TVU. CL change across three time points was assessed using linear mixed models; then relationships between CL change between 16-19 and 19-22 weeks and PTB were analysed using logistic regression models.

RESULTS

Term birth was most likely when CL did not decrease across both time periods. The addition of 16-19 week decrease in CL to a model, including CL at 19 weeks alone, for predicting PTB increased sensitivity from 43.2 to 56.3%, specificity from 73.2 to 77.4%, and overall accuracy from 61.7 to 70.2%.

CONCLUSION

For high-risk women prescribed vaginal progesterone therapy, serial measurement of the cervix at 16 and 19 weeks improves clinical ability to predict PTB from current recommendations of 19-week measurement alone.

The effectiveness of vaginal progesterone in reducing preterm birth in high-risk patients diagnosed with short cervical length after 24 weeks: A retrospective cohort study

Objective

To assess the impact of progesterone treatment on maternal and neonatal outcomes in women with a history of preterm birth and short cervical length diagnosed after 24 weeks of gestation.

Methods

A retrospective cohort study included women with a history of preterm birth and a transvaginal sonographic cervical length measurement of ≤ 25 mm, diagnosed between 24+0 and 33+6 weeks of gestation. Exclusion criteria included prior progesterone treatment, cervical cerclage, or pessary. The study population was divided into the progesterone treatment group and the non-treatment group.

Results

The study included 104 women, with 46.2% (48/104) receiving progesterone treatment and 53.8% (56/104) not receiving treatment. The rate of spontaneous preterm birth before 37 weeks of gestation was 43% (24/56) in the non-treatment group and 31% (15/48) in the progesterone treatment group (P = 0.14); the rate of spontaneous preterm birth before 34 weeks was 7% (4/56) in the non-treatment group and 0% (0/48) in the progesterone treatment group (P = 0.05). Progesterone treatment was associated with a significant decrease in neonatal intensive care unit admissions (OR 0.20, 95% CI 0.05-0.74) and in the neonatal hospitalization period (mean difference in days 2.43, 95% CI 0.44-4.42). The risk of recurrent spontaneous preterm birth was highest (71%) among women with two or more previous preterm deliveries who did not receive progesterone treatment, and lowest (24%) among women with one previous preterm delivery who received progesterone treatment.

Conclusion

Progesterone treatment was associated with a reduction in rates of spontaneous preterm birth before 34 weeks of gestation, neonatal intensive care unit admission, and neonatal length of stay in high-risk patients, even when initiated after 24 weeks of gestation.

Incidentally Found Midtrimester Shortened Cervical Length: Practice Patterns among American Maternal-Fetal Medicine Specialists

OBJECTIVE

The management of incidentally found short cervical length (CL) without prior spontaneous preterm birth (PTB) can vary. While most agree on starting vaginal progesterone, management after CL shortens <10 mm varies. The purpose of this study was to elucidate current practice patterns amongst maternal-fetal medicine (MFM) specialists.

STUDY DESIGN

We conducted an online survey of MFM attending physicians and fellows in the United States from May 2019 to April 2020. The primary outcome was management of varying CL based on gestational age. Variations in management were assessed descriptively.

RESULTS

There were 236 respondents out of 400 eligible surveyed, with a response rate of 59.2%. Universal CL screening was reported by 93.6% (49.6% abdominal and 44.1% transvaginal). Management of short CL varied based on CL measurement, rather than gestational age at presentation. At CL <10 mm, management included cerclage (17.4-18.7%), vaginal progesterone (41.3-41.7%), or cerclage plus vaginal progesterone (43.4%). Between CL of 10 to 20 mm, the majority (77.4-91.9%) would start vaginal progesterone. At CL 21 to 25 mm, management varied between expectant management (45.5-48.5%) or vaginal progesterone (51.1-52.8%). Suture material used was ethylene terephthalate (47.4%) or polypropelene (31.2). Preoperative antibiotic use was reported by 22.3%, while 45.5% used them only if the amniotic membranes were exposed, and 32.2% reported no antibiotic use. Postoperative tocolytic use varied with 19.3% reporting no use, 32.6% using it always, 8.2% only after significant cervical manipulation, 22.7% after the patient is experiencing symptoms, and 17.6% using it only if the cervix is dilated on exam. After cerclage placement, 44.5% continued CL surveillance.

CONCLUSION

Substantial differences of opinion exist among MFM physicians regarding management of incidentally found short CL in patients without history of PTB. The differences in responses obtained highlight the need for evidence-based guidelines for managing this clinical scenario.

KEY POINTS

· There is lack of consensus on the management of incidentally found shortened CL.. · The purpose of this study was to elucidate current trends in CL screening and management.. · Substantial differences of opinion exist regarding management of incidentally found short CL..

The introduction of a universal transvaginal cervical length screening program is associated with a reduced preterm birth rate

BACKGROUND

Midtrimester sonographic short cervix is a good predictor of preterm birth in singleton pregnancies.

OBJECTIVE

This study aimed to assess the impact of implementing a universal transvaginal cervical length screening program on preterm birth rate.

STUDY DESIGN

This study consisted of 2 parts: a before-and-after multicenter study and a study on the ECHOCOL ("echo"="ultrasound" and "col"="cervix" in French) prospective cohort. We compared the rate of preterm birth before and after the introduction of universal cervical length screening at the time of midtrimester anatomy ultrasound. The multicenter before-and-after regional study included all women with a singleton pregnancy who gave birth after 24 weeks' gestation in the South East of France from January 1, 2012 to April 30, 2018. In parallel, the ECHOCOL cohort study was prospectively conducted from May 2015 to July 2018, including 17 maternity hospitals in the South East region of France. In case of asymptomatic short cervix <25 mm, treatments offered included 200 mg of vaginal progesterone, or cerclage, or a pessary until 34 weeks' gestation.

RESULTS

We observed a significant decrease rate of preterm birth between periods A and B after multivariate analysis. (respectively, 5.8% vs 5.6%; adjusted odds ratio, 0.92; 95% confidence interval, 0.89-0.95; P<.0001). In parallel, the percentage of cervical length screening significantly increased from 28.9% in period A to 52.9% in period B (odds ratio, 2.76; 95% confidence interval, 2.71-2.80; P<.0001). Among the 3468 patients of the ECHOCOL prospective cohort, 38 (1.1%) asymptomatic short cervices were detected, and 192 patients gave birth prematurely (11 with an asymptomatic short cervix and 181 without). In the ECHOCOL cohort, a marked but statistically insignificant tendency toward a reduced rate of preterm birth before 37 weeks of gestation was observed (from 5.8% to 5.5%; adjusted odds ratio, 0.72; 95% confidence interval, 0.51-1.03; P=.068).

CONCLUSION

This study showed a significantly lower rate of preterm birth after the implementation of a universal cervical length screening and treating policy during the second trimester of pregnancy. The clinical trial was registered under NCT02598323.

Role of progesterone on dexamethasone-induced alterations in placental vascularization and progesterone receptors in rats†

BACKGROUND

Intrauterine growth restriction (IUGR) is manifested by lower maternal progesterone levels, smaller placental size, and decreased placental vascularity indicated by lower expression of vascular endothelial growth factor (VEGF). Studies showed that progesterone increases angiogenesis and induces VEGF expression in different tissues. Therefore, the aim of the present study is to evaluate the effect of progesterone on placental vascular bed and VEGF expression and the modulation of nuclear and membranous progesterone receptors (PR) in dexamethasone-induced rat IUGR model.

METHODS

Pregnant Sprague-Dawley rats were allocated into four groups and given intraperitoneal injections of either saline, dexamethasone, dexamethasone, and progesterone or progesterone. Injections started on gestation day (DG) 15 and lasted until the days of euthanization (19 and 21 DG). Enzyme-linked immunosorbent assay was used to evaluate plasma progesterone levels. Real-time PCR and western blotting were used to evaluate gene and protein expressions of VEGF, and PR in labyrinth and basal placental zones. Immunohistochemistry was used to locate VEGF and different PRs in placental cells. Immunofluorescence was used to monitor the expression of blood vessel marker (αSMA).

RESULTS

Dexamethasone decreased the vascular bed fraction and the expression of VEGF in both placental zones. Progesterone co-treatment with dexamethasone prevented this reduction. Nuclear and membrane PRs showed tissue-specific expression in different placental zones and responded differently to both dexamethasone and progesterone.

CONCLUSIONS

Progesterone treatment improves the outcomes in IUGR pregnancy. Progesterone alleviated DEX-induced IUGR probably by promoting placental VEGF and angiogenesis.

Resolution of acute cervical insufficiency after antibiotics in a case with amniotic fluid sludge

Cervical insufficiency generally refers to a condition in which there is mid-trimester cervical dilatation or protruding chorioamniotic membranes in the absence of uterine contractions. Such condition is a risk factor for spontaneous mid-trimester abortion or early preterm birth, and is associated with adverse neonatal outcomes. Both intra-amniotic infection and inflammation ascertained by amniocentesis have been identified in patients with cervical insufficiency, and are poor prognostic factors. A subset of patients with intra-amniotic inflammation will have no demonstrable microorganisms detected via cultivation or molecular methods, and therefore represent cases of sterile intra-amniotic inflammation. Amniotic fluid sludge (free-floating hyperechogenic material within the amniotic fluid in close proximity to the uterine cervix) identified on sonography is a biomarker for intra-amniotic infection and inflammation. Recent evidence suggests that intra-amniotic infection, as well as sterile intra-amniotic inflammation can be treated successfully using antimicrobial agents. We report a unique case in which administration of antibiotics in the presence of mid-trimester cervical insufficiency, sterile intra-amniotic inflammation, and amniotic fluid sludge was associated with resolution of the cervical findings, as demonstrated on both sonographic and speculum examination. The patient successfully underwent elective cesarean delivery at 36-2/7 weeks of gestation. This case illustrates that antibiotic therapy may be effective despite the presence of several high-risk pregnancy conditions, and that successful outcome is possible.

Epithelial to mesenchymal transition (EMT) of feto-maternal reproductive tissues generates inflammation: a detrimental factor for preterm birth

Human pregnancy is a delicate and complex process where multiorgan interactions between two independent systems, the mother, and her fetus, maintain pregnancy. Intercellular interactions that can define homeostasis at the various cellular level between the two systems allow uninterrupted fetal growth and development until delivery. Interactions are needed for tissue remodeling during pregnancy at both fetal and maternal tissue layers. One of the mechanisms that help tissue remodeling is via cellular transitions where epithelial cells undergo a cyclic transition from epithelial to mesenchymal (EMT) and back from mesenchymal to epithelial (MET). Two major pregnancy-associated tissue systems that use EMT, and MET are the fetal membrane (amniochorion) amnion epithelial layer and cervical epithelial cells and will be reviewed here. EMT is often associated with localized inflammation, and it is a well-balanced process to facilitate tissue remodeling. Cyclic transition processes are important because a terminal state or the static state of EMT can cause accumulation of proinflammatory mesenchymal cells in the matrix regions of these tissues and increase localized inflammation that can cause tissue damage. Interactions that determine homeostasis are often controlled by both endocrine and paracrine mediators. Pregnancy maintenance hormone progesterone and its receptors are critical for maintaining the balance between EMT and MET. Increased intrauterine oxidative stress at term can force a static (terminal) EMT and increase inflammation that are physiologic processes that destabilize homeostasis that maintain pregnancy to promote labor and delivery of the fetus. However, conditions that can produce an untimely increase in EMT and inflammation can be pathologic. These tissue damages are often associated with adverse pregnancy complications such as preterm prelabor rupture of the membranes (pPROM) and spontaneous preterm birth (PTB). Therefore, an understanding of the biomolecular processes that maintain cyclic EMT-MET is critical to reducing the risk of pPROM and PTB. Extracellular vesicles (exosomes of 40-160 nm) that can carry various cargo are involved in cellular transitions as paracrine mediators. Exosomes can carry a variety of biomolecules as cargo. Studies specifically using exosomes from cells undergone EMT can carry a pro-inflammatory cargo and in a paracrine fashion can modify the neighboring tissue environment to cause enhancement of uterine inflammation.

Clinical Value and Treatment Progress of Prenatal Ultrasonography in Twin Pregnancy: A Systematic Review

Assisted reproductive technology has continued to develop in recent years, the technology has become more and more mature, and it has improved the total gestational age of the population. Assisted reproductive technology has improved twin pregnancy rates with the use of ovulation-inducing drugs. The risk factor of twins is much higher than singletons, and adverse pregnancy outcomes such as stillbirth and premature birth are more likely to occur than singletons, especially the special complications of monochorionic twins (MC), and the neonatal mortality and morbidity are also increased. Prenatal diagnosis and prognosis of twin pregnancy, as well as therapeutic interventions, are of current concern. Ultrasound can realize the understanding of intrauterine growth and development of twin pregnancy fetuses during pregnancy, can more accurately determine gestational age, organ function, and maturity, and timely detect fetal growth and development abnormalities in twin pregnancy, while the prognosis and treatment still need further improvement. The purpose of this study was to investigate the clinical value and treatment progress of prenatal ultrasound monitoring in twin pregnancy.

Recurrent Preterm Birth Reduction by 17-Hydroxyprogesterone Caproate in Dichorionic/Diamniotic Twin Gestation

OBJECTIVE

The study aimed to evaluate the impact of 17-hydroxyprogesterone caproate (17-OHPC) on recurrent preterm birth (PTB) in women with a prior PTB and a current dichorionic/diamniotic twin gestation.

STUDY DESIGN

We combined individual patient-level data from two prospective randomized placebo-controlled trials of prophylactic 17-OHPC in twin gestation and compared the rates of recurrent spontaneous PTB in those women with a prior singleton PTB randomized to placebo or 17-OHPC (250 mg weekly).

RESULTS

Only 7.4% of women with dichorionic/diamniotic twin gestation experienced a prior PTB. Among these 66 women, spontaneous delivery prior to 34 weeks occurred significantly less often (p = 0.03) in those randomized to 17-OHPC (20.6%) than in those randomized to placebo (46.9%). However, mean gestational length was not significantly different, and there was no statistically significant difference in composite neonatal outcome.

CONCLUSION

17-OHPC may be beneficial to women with a prior PTB and a current dichorionic/diamniotic twin gestation. These findings along with those reported by the Maternal Fetal Medicine Units Network in singletons suggest a common mechanism of action and a specific target population, those with a prior PTB, that may benefit from 17-OHPC treatment. A large prospective trial is needed to validate these findings.

KEY POINTS

· 17-OHPC reduces recurrent PTB in women with dichorionic/diamniotic twins.. · PTB risk and response to 17-OHPC may differ according to the type of twinning.. · 17-OHPC may affect a common pathway in twins and singletons with a prior PTB..

A Review of Delayed Delivery Models and the Analysis Method in Mice

In humans, the incidence of post-term delivery is 1–10%. Post-term delivery significantly increases the risk of cesarean section or neonatal intensive care unit (NICU) admission. Despite these serious challenges, the cause of prolonged delivery remains unclear. Several common factors of delayed parturition between mice and humans will help elucidate the mechanisms of pregnancy and labor. At present, gene modification techniques are rapidly developing; however, there are limited reviews available describing the mouse phenotype analysis as a human model for post-term delivery. We classified the delayed-labor mice into nine types according to their causes. In mice, progesterone (P₄) maintains pregnancy, and the most common cause of delayed labor is luteolysis failure. Other contributing factors include humoral molecules in the fetus/placenta, uterine contractile dysfunction, poor cervical ripening, and delayed implantation. The etiology of delayed parturition is overexpression of the pregnancy maintenance mechanism or suppression of the labor induction mechanism. Here, we describe how to investigated their causes using mouse genetic analysis. In addition, we generated a list to identify the causes. Our review will help understand the findings obtained using the mouse model, providing a foundation for conducting more systematic research on delayed delivery.

Interventions to Prevent Bronchopulmonary Dysplasia in Preterm Neonates: An Umbrella Review of Systematic Reviews and Meta-analyses

IMPORTANCE

Bronchopulmonary dysplasia (BPD) has multifactorial etiology and long-term adverse consequences. An umbrella review enables the evaluation of multiple proposed interventions for the prevention of BPD.

OBJECTIVE

To summarize and assess the certainty of evidence of interventions proposed to decrease the risk of BPD from published systematic reviews.

DATA SOURCES

MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, and Web of Science were searched from inception until November 9, 2020.

STUDY SELECTION

Meta-analyses of randomized clinical trials comparing interventions in preterm neonates that included BPD as an outcome.

DATA EXTRACTION AND SYNTHESIS

Data extraction was performed in duplicate. Quality of systematic reviews was evaluated using Assessment of Multiple Systematic Reviews version 2, and certainty of evidence was assessed using Grading of Recommendation, Assessment, Development, and Evaluation.

MAIN OUTCOMES AND MEASURES

(1) BPD or mortality at 36 weeks' postmenstrual age (PMA) and (2) BPD at 36 weeks' PMA.

RESULTS

A total of 154 systematic reviews evaluating 251 comparisons were included, of which 110 (71.4%) were high-quality systematic reviews. High certainty of evidence from high-quality systematic reviews indicated that delivery room continuous positive airway pressure compared with intubation with or without routine surfactant (relative risk [RR], 0.80 [95% CI, 0.68-0.94]), early selective surfactant compared with delayed selective surfactant (RR, 0.83 [95% CI, 0.75-0.91]), early inhaled corticosteroids (RR, 0.86 [95% CI, 0.75-0.99]), early systemic hydrocortisone (RR, 0.90 [95% CI, 0.82-0.99]), avoiding endotracheal tube placement with delivery room continuous positive airway pressure and use of less invasive surfactant administration (RR, 0.90 [95% CI, 0.82-0.99]), and volume-targeted compared with pressure-limited ventilation (RR, 0.73 [95% CI, 0.59-0.89]) were associated with decreased risk of BPD or mortality at 36 weeks' PMA. Moderate to high certainty of evidence showed that inhaled nitric oxide, lower saturation targets (85%-89%), and vitamin A supplementation are associated with decreased risk of BPD at 36 weeks' PMA but not the competing outcome of BPD or mortality, indicating they may be associated with increased mortality.

CONCLUSIONS AND RELEVANCE

A multipronged approach of delivery room continuous positive airway pressure, early selective surfactant administration with less invasive surfactant administration, early hydrocortisone prophylaxis in high-risk neonates, inhaled corticosteroids, and volume-targeted ventilation for preterm neonates requiring invasive ventilation may decrease the combined risk of BPD or mortality at 36 weeks' PMA.

Cerclage versus vaginal progesterone in low-risk pregnant women with a short cervix

OBJECTIVE

To compare vaginal progesterone to cerclage in preventing preterm birth and adverse perinatal outcomes in women with a singleton gestation, incidentally found sonographic cervical length of <15 mm, and no history of preterm birth.

STUDY DESIGN

A retrospective cohort study was conducted on 68 women who delivered at the University of Kansas Health System with a singleton gestation found to have a cervical length <15 mm on transvaginal ultrasound and no history of preterm birth. Women treated with vaginal progesterone (n = 29) were compared to women who underwent cerclage placement (n = 39). The primary outcome was preterm birth at <34 weeks of gestation. Secondary outcomes include preterm birth at <37 and <28 weeks of gestation and neonatal morbidities.

RESULTS

Of the 268 patients who had a cervical length of <15 mm on transvaginal ultrasound, 68 participants met inclusion criteria and were included in the final analysis. Twenty-nine participants received vaginal progesterone and 39 participants received cervical cerclage. The average cervical length at initiation of therapy was greater in the progesterone cohort versus cerclage cohort, respectively (10.5 vs. 8.0 mm, p < .01). All other baseline characteristics were similar between groups, including no difference in average gestational age at initiation of therapy (21.6 vs. 21.5 weeks, p = .87). Average latency after therapy did not differ between groups (100 vs. 92.7 days p = .43). The incidence of preterm birth at <37 weeks (OR = 1.49, 95% CI = 0.57-3.93), <34 weeks (OR = 1.47, 95% CI = 0.52-4.18), and <28 weeks (OR = 1.90, 95% CI = 0.45-8.07), did not differ significantly between groups. Additionally, no difference in neonatal morbidity was detected.

CONCLUSION

At our institution, we found no difference between vaginal progesterone and cerclage in the average latency period or risk of preterm birth among women with an incidental short cervix of <15 mm and no history of preterm birth, despite the significantly shorter initial cervical length in the cerclage group. These findings suggest either vaginal progesterone or cerclage could be used to reduce the risk of preterm birth among this high-risk population.

Prediction of Preterm Birth with Serial Measurements of Ultrasound Markers

To compare the ability of cervical length (CL), anterior cervical angle (ACA), and cervical consistency index (CCI) to predict premature birth.

METHODS

This prospective study involved 85 pregnant women who gave birth prematurely and a control group of 31 pregnant women who gave birth at term. The study was performed in the Obstetrics and Gynecology Clinic of the Municipal Clinical Hospital Filanthropia Craiova between January 1, 2019, and January 1, 2022. Cases were examined using transvaginal ultrasonography (TVU) in the second and third trimesters of pregnancy, and cervical length (CL), Anterior Cervical Angle (ACA), and Cervical Consistency Index (CCI) were measured.

RESULTS

The mean value from the three measurements at all three parameters was statistically significant with preterm birth (p<0.05). Cervical length <25mm, was highly significant in the prediction of preterm labor with a sensitivity of 99%, specificity of 61%, positive predictive value (PPV) of 78%, negative predictive value (NPV) of 97 %, and a positive likelihood ratio (LR+) of 2.54 and negative likelihood ratio (LR-) of 0.02. CCI also remains, despite low specificity and PPV values, a potential predictive parameter in the prediction of preterm birth, with a sensitivity of 73%, NPV of 92% and a LR+of 1.32 and LR- of 0.6 also correlated with CL, CCI being more difficult to interpret as an independent predictive parameter.

CONCLUSIONS

CL remains the standard parameter for predicting the preterm birth, but in combination with other parameters, the prediction rate can increase significantly.

Progesterone partially recovers placental glucose transporters in dexamethasone-induced intrauterine growth restriction

RESEARCH QUESTION

How does progesterone improve fetal outcome and change the expression of placental glucose transporters (GLUT) in dexamethasone-induced intrauterine growth restriction (IUGR)?

DESIGN

A total of 64 rats were divided randomly into four different treatment groups based on daily i.p. injections of either saline or dexamethasone in the presence or absence of progesterone. Injections started on the 15th day of gestation (15dg) and lasted until the day of sacrifice at 19dg or 21dg. Maternal plasma progesterone concentrations were measured by enzyme-linked immunosorbent assay. The gene and protein expression of placental GLUT1 and GLUT3 were evaluated in the placental labyrinth and basal zones by real-time polymerase chain reaction and Western blotting, respectively. The localization of GLUT1 and GLUT3 was evaluated by immunohistochemistry.

RESULTS

Dexamethasone induced significant decreases in maternal serum progesterone concentrations (P = 0.029) and placental (P < 0.001) and fetal body (P = 0.009) weights. Dexamethasone also reduced the expression of GLUT1 in the labyrinth zone (P = 0.028) and GLUT3 in both the labyrinth (P = 0.002) and basal zones (P = 0.026). Coadministration of dexamethasone and progesterone prevented the reduction in fetal body weight, placental weight and placental GLUT expression compared with that seen in dexamethasone-treated groups.

CONCLUSION

These results suggest that progesterone prevents the significant reduction in fetal and placental weights in dexamethasone-induced IUGR, possibly through improving the expression of placental GLUT.

A randomized controlled trial of two-doses of vaginal progesterone 400 vs. 200 mg for prevention of preterm labor in twin gestations

OBJECTIVES

To compare between the effectiveness and safety of two different daily doses of vaginal progesterone (400 vs. 200 mg) in the prevention of preterm labor in twin pregnancy.

METHODS

This is a prospective single-blinded randomized controlled trial conducted on 100 primi-gravida who had twin pregnancy and attended the antenatal clinic of a University hospital. They were equally and randomly allocated into two arms each containing 50 patients. Arm 1 received 400 mg and arm 2 received 200 mg vaginal progesterone daily at bed time starting from 14 weeks of pregnancy to 36 weeks. Transvaginal ultrasound was performed for assessment of the length of cervix at 14 and 22 weeks.

RESULTS

Both arms of the current study were comparable regarding the cervical length at 14 and 22 weeks, mean gestational age at delivery, incidence of pre-term delivery, birth weight of the first twin. Second twin in addition to the average weight of both twins. No statistical significance differences between two arms regarding incidence of early neonatal death. NICU, mechanical ventilation, length of admission in NICU for the first twin. Second twin as well as both twins.

CONCLUSIONS

Vaginal progesterone treatment with different doses was tolerable, but wasn't effective in the prevention of preterm labor in twin pregnancy.

Study protocol to quantify the genetic architecture of sonographic cervical length and its relationship to spontaneous preterm birth

INTRODUCTION

A short cervix (cervical length <25 mm) in the midtrimester (18-24 weeks) of pregnancy is a powerful predictor of spontaneous preterm delivery. Although the biological mechanisms of cervical change during pregnancy have been the subject of extensive investigation, little is known about whether genes influence the length of the cervix, or the extent to which genetic factors contribute to premature cervical shortening. Defining the genetic architecture of cervical length is foundational to understanding the aetiology of a short cervix and its contribution to an increased risk of spontaneous preterm delivery.

METHODS/ANALYSIS

The proposed study is designed to characterise the genetic architecture of cervical length and its genetic relationship to gestational age at delivery in a large cohort of Black/African American women, who are at an increased risk of developing a short cervix and delivering preterm. Repeated measurements of cervical length will be modelled as a longitudinal growth curve, with parameters estimating the initial length of the cervix at the beginning of pregnancy, and its rate of change over time. Genome-wide complex trait analysis methods will be used to estimate the heritability of cervical length growth parameters and their bivariate genetic correlation with gestational age at delivery. Polygenic risk profiling will assess maternal genetic risk for developing a short cervix and subsequently delivering preterm and evaluate the role of cervical length in mediating the relationship between maternal genetic variation and gestational age at delivery.

ETHICS/DISSEMINATION

The proposed analyses will be conducted using deidentified data from participants in an IRB-approved study of longitudinal cervical length who provided blood samples and written informed consent for their use in future genetic research. These analyses are preregistered with the Center for Open Science using the AsPredicted format and the results and genomic summary statistics will be published in a peer-reviewed journal.

Evaluation of Uterocervical Angle and Cervical Length as Predictors of Spontaneous Preterm Birth

Aim The aim of this article was to evaluate uterocervical angle (UCA) and cervical length (CL) measured at 16 to 24 weeks of gestation using transvaginal sonography (TVS) as predictors of spontaneous preterm birth.

Methods In this prospective study, TVS was performed in 159 primigravidas with a singleton, uncomplicated pregnancy at 16 to 24 weeks of gestation to measure the anterior UCA and CL. All the cases were followed until labor to document gestational age at delivery.

Results The risk of spontaneous preterm birth was higher in women with obtuse UCA (>95 degrees) with sensitivity of 86.7%, specificity of 93.0%, positive predictive value of 83.0%, negative predictive value of 94.6%, and p-value of <0.001. The difference between the means was statistically significant (p-value < 0.001). UCAs ≥105degrees and 95 to 105 degrees were found to be significantly associated with spontaneous preterm births at <34 weeks and 34 to 37 weeks, respectively. CL <2.5 cm was found to predict spontaneous preterm births at <37 weeks with sensitivity of 31.1%, specificity of 95.6%, and p-value of <0.001. UCA was found to be a better predictor of spontaneous preterm birth with a higher coefficient of variation (56.4%) when compared with CL (16.9%).

Conclusions UCA proved to be a novel ultrasound parameter that can serve as a better predictor of spontaneous preterm births in comparison to CL. A strong correlation exists between obtuse UCA and a risk of spontaneous preterm birth.

The effect of progesterone administration on the expression of metastasis tumor antigens (MTA1 and MTA3) in placentas of normal and dexamethasone-treated rats

BACKGROUND

Dexamethasone (DEX) induces intrauterine growth restriction (IUGR) in pregnant rats. IUGR can occur due to apoptosis of trophoblasts, which is believed to be inhibited by progesterone (P4). A group of genes called MTAs play a role in proliferation and apoptosis. MTA1 upregulates trophoblasts proliferation and differentiation, while MTA3 downregulates proliferation and induces apoptosis. Hence, we hypothesized that during IUGR, placental MTA1 decreases and MTA3 increases and this is reversed by P4 treatment.

METHODS

Pregnant Sprague-Dawley rats were divided into 4 groups based on daily intraperitoneal injections: control (C, saline), DEX (DEX, 0.2 mg/kg/day), DEX and P4 (DEX + P4, DEX: 0.2 mg/kg/day, P4: 5 mg/kg/day) and P4-treated (P4, 5 mg/kg/day) groups. Injections were started on 15 dg until the day of dissection (19 or 21 dg). Gene and protein expressions of MTA1 and MTA3 were studied in the labyrinth (LZ) and basal (BZ) zones using real-time PCR and Western blotting, respectively.

RESULTS

DEX treatment induced 18% reduction in fetal body weight (p < 0.001) and 30% reduction in placental weight (p < 0.01). Maternal P4 level was also significantly lower in DEX treated groups (p < 0.05). MTA1 expression was decreased in the LZ (gene, p < 0.001) and BZ (protein p < 0.01), while MTA3 protein expression was upregulated in the LZ with DEX treatment (p < 0.001). These changes were reversed with P4 treatment.

CONCLUSION

The findings of the present study indicate that DEX induces IUGR through changing the expression of placental MTA1 and MTA3 antigens and P4 improved pregnancy outcome by preventing the changes in MTAs expression.

Pessary Plus Progesterone to Prevent Preterm Birth in Women With Short Cervixes: A Randomized Controlled Trial

OBJECTIVE

To test the effectiveness of cervical pessary in addition to vaginal progesterone for the prevention of preterm birth in women with midpregnancy short cervixes.

METHODS

We performed a multicenter, open-label, randomized controlled trial in 17 perinatal centers. Asymptomatic women with singleton or twin pregnancies and cervical lengths of 30 mm or less, measured at 18 0/7-22 6/7 weeks of gestation, were randomized to cervical pessary plus vaginal progesterone (pessary plus progesterone group) or vaginal progesterone only (progesterone-only group) (200 mg/day). Treatments were used from randomization to 36 weeks of gestation or delivery. The primary outcome was a composite of neonatal mortality and morbidity. Secondary outcomes were delivery before 37 weeks and before 34 weeks of gestation. Analysis was performed according to intention to treat.

RESULTS

Between July 9, 2015, and March 29, 2019, 8,168 women were screened, of whom 475 were randomized to pessary and 461 to progesterone only. The composite perinatal outcome occurred in 19.2% (89/463) of the women in the pessary group compared with 20.9% (91/436) of the women in the progesterone-only group (adjusted risk ratio [aRR] 0.88, 95% CI 0.69-1.12). Delivery rates before 37 weeks of gestation were 29.1% compared with 31.4% (aRR 0.86, 95% CI 0.72-1.04); delivery rates before 34 weeks were 9.9% compared with 13.9% (aRR 0.66, 95% CI 0.47-0.93). Women in the pessary group had more vaginal discharge (51.6% [245/476] vs 25.4% [117/479] [P<.001]), pain (33.1% [157/476] vs 24.1% [111/479] [P=.002]), and vaginal bleeding (9.7% [46/476] vs 4.8% [22/479] [P=.004]).

CONCLUSION

In asymptomatic women with short cervixes, the combination of pessary and progesterone did not decrease rates of neonatal morbidity or mortality when compared with progesterone only.

CLINICAL TRIAL REGISTRATION

Brazilian Clinical Trial Registry (ReBec), UTN:U1111-1164-2636.

Comparison the efficacy of vaginal progesterone versus 17-alpha-hydroxyprogesterone caproate to prevent preterm birth in high-risk pregnant women undergo cerclage: a randomized clinical trial

OBJECTIVE

The aim of this study was to compare the effect of vaginal progesterone with 17-alpha-hydroxyprogesterone caproate (17OHP-C) in prevention of preterm birth in high-risk pregnant women undergo cerclage.

MATERIALS AND METHODS

This prospective randomized clinical trial registered in the Iranian Registry of Clinical Trials (IRCT20181107041585N4), was performed from May 2017 to August 2018 in Bandar Abbas, Iran. Fifty-eight eligible women who were scheduled for cervical cerclage due to a history of two or more previous preterm birth <28 weeks or a cervical length less than 25 mm with at least one previous preterm birth <34 weeks were randomly divided into two groups. The first group received 200 mg of vaginal progesterone suppository daily and the second one received 250 mg of 17OHP-C intramuscular weekly after cerclage procedure until the end of 36 weeks. Patients were followed up to the end of delivery and the newborn until the first 28 d after delivery.

RESULTS

Gestational age at the time of birth in 17OHP-C group was significantly higher than vaginal progesterone group (p=.021). However, the incidence of preterm birth in both groups was not statistically significant (20.7% vs. 24.1%). Apgar scores, newborn birthweight, admission to neonatal intensive care unit (NICU), incidence of respiratory distress syndrome (RDS), sepsis, necrotizing enterocolitis (NEC), and, intraventricular hemorrhage (IVH), was similar in both groups. Adverse events were reported in 48.3% of patients in 17-OHP-C group, and 27.6% of patients in the vaginal progesterone group (p= .014).

CONCLUSIONS

Vaginal progesterone and 17OHP-C had similar results in terms of prevention of preterm birth and neonatal outcome. However, the adverse events associated with 17-OHP-C were higher than vaginal progesterone.