Effect of progestogen for women with threatened miscarriage: a systematic review and meta‐analysis

PERİDER-TJOD joint review on threatened abortion and guideline for its treatment

Objective

Although there are several guidelines in the literature on "recurrent abortion", there is no comprehensive guideline on "threatened abortion". The overall purpose of this guideline is to provide healthcare providers with the best available evidence for examination and treatment of pregnant women with threatened abortion.

Materials and Methods

The scope of the guideline and the first version of the questions were prepared by the Perinatology and High Risk Pregnancies Association (PERİDER) guideline development group in January 2024. Meetings were held to discuss key questions and redefine them. A final list of 8 key questions was created. Keywords were defined for each question and ranked in order of importance and used in searches for all English-language publications in PubMed/Medline and Cochrane libraries. These databases were thoroughly scanned for publications that were published until February 1, 2024. Literature reviews were conducted as an iterative process. In the first step, systematic reviews and meta-analyses were collected. If no results were found, the research was expanded to randomized controlled trials and then to cohort studies and case reports, following the hierarchy of evidence levels.

Results

This guideline was presented to the board of directors of the Turkish Gynecology and Obstetrics Society (TJOD). With their suggestions, guideline was finalized, and it was decided to be published as a joint guideline of PERİDER-TJOD.

Conclusion

This guideline provides an overview of threatened abortion and the recommended treatments. In addition, by recognizing the deficiencies in the literature, suggestions were made regarding research that could help clinicians' decisions in the future.

Progestogens in women with threatened miscarriage or recurrent miscarriage: A meta-analysis

INTRODUCTION

Clinical practice guidelines provide inconsistent recommendations regarding progestogen supplementation for threatened and recurrent miscarriage. We conducted a systematic review and meta-analysis to assess the effectiveness and safety of progestogens for these patients.

MATERIAL AND METHODS

We searched Medline, Embase, and Cochrane Central Registry of Controlled Trials up to October 6, 2023 for randomized control trials (RCTs) comparing progestogen supplementation to placebo or no treatment for pregnant women with threatened or recurrent miscarriage. We assessed the risk of bias using a modified version of the Cochrane risk-of-bias tool and the certainty of evidence using the GRADE approach.

RESULTS

Of 15 RCTs (6616 pregnancies) reporting on threatened or recurrent miscarriage, 12 (5610 pregnancies) reported on threatened miscarriage with or without a prior history of miscarriage. Results indicated that progesterone probably increases live births (relative risk (RR) 1.04, 95% confidence interval (CI) 0.99-1.10, absolute increase 3.1%, moderate certainty). Of these RCTs, three (1973 pregnancies) reporting on threatened miscarriage with a prior history of miscarriage indicated that progesterone possibly increases live births (RR 1.06, 95% CI: 0.97-1.16, absolute increase 4.4%; low certainty), while four (2540 pregnancies) reporting on threatened miscarriage and no prior miscarriage left the effect very uncertain (RR 1.02, 95% CI: 0.96-1.10, absolute increase 1.7%; very low certainty). Three trials reporting on 1006 patients with a history of two or more prior miscarriages indicated progesterone probably increases live births (RR 1.08, 95% CI: 0.98-1.19, absolute increase 5.7%, moderate certainty). Six RCTs that reported on 2979 patients with at least one prior miscarriage indicated that progesterone probably increases live births (RR 1.07, 95% CI: 1.01-1.13, absolute increase 5.0%; moderate certainty). Progesterone probably has little or no effect on congenital anomalies (RR 1.06, 95% CI: 0.76-1.48, absolute increase 0.1%; moderate certainty), and other serious adverse pregnancy events (RR 1.07, 95% CI: 0.83-1.40, absolute increase 0.2%, moderate certainty).

CONCLUSIONS

In women at increased risk of pregnancy loss, progestogens probably increase live births without increasing adverse maternal and neonatal events. It remains possible that the benefit is restricted to those with prior miscarriages.

Short-term effects of exposure to ambient PM2.5 and its components on hospital admissions for threatened and spontaneous abortions: A multicity case-crossover study in China

BACKGROUND

The adverse effects of short-term exposure to PM2.5 and its components on hospital admissions for threatened and spontaneous abortions (TSAB) are still controversial.

METHODS

Data on daily hospitalizations for TSAB and PM2.5 and its components, including sulfate (SO42-), nitrate (NO3-), ammonium salt (NH4+), organic matter (OM), and black carbon (BC), were collected from January 2015 to December 2021 (total 2,557 days) in five cities in China. Case-crossover analyses were conducted to investigate the short-term associations between PM2.5 and its components and TSAB. Additionally, the modification effects by age (<35 and ≥35 years), season (cold and warm seasons), and the "Three-Year Action Plan to Win the Blue Sky Defense War" (before and after implementation) on the above associations were further conducted.

RESULTS

For each 10 μg/m3 (1 μg/m3 for BC) increase, the strongest relative risks (95% confidence intervals) of hospitalization for TSAB were 1.011 (1.001-1.021) for PM2.5 in lag02, 1.060 (1.003-1.120) for SO42- in lag02, 1.035 (1.000-1.070) for NO3- in lag02, 1.065 (1.009-1.124) for NH4+ in lag02, 1.047 (1.008-1.088) for OM in lag01 and 1.029 (1.005-1.054) for BC in lag02 (all P <0.05). Furthermore, significant modifying effects of age and the Action Plan were found. The effects of NO3- (lag2), NH4+ (lag2), and BC (lag2) were more pronounced in mothers aged ≥35 years and the effects of PM2.5 (lag4), NO3- (lag4), NH4+ (lag4), OM (lag4), and BC (lag4) was more pronounced in the period before the Action Plan was implemented (all P modification <0.05).

CONCLUSION

Short-term exposure to ambient PM2.5 and its components (SO42-, NO3-, NH4+, OM, and BC) was related to increased risks of hospitalization for TSAB. The effects were more pronounced in mothers aged ≥35 years and the period before the Action Plan.

Shoutai Wan regulates glycolysis imbalance at the maternal-fetal interface in threatened abortion mice

ETHNOPHARMACOLOGICAL RELEVANCE

Threatened abortion is a common disease among women of childbearing age. Its high incidence rate and unclear etiology, seriously threaten women's physical and mental health. Shoutai Wan (STW) is a traditional Chinese medicine decoction for treating abortion. It has a long history of treating threatened abortion by tonifying the kidney and calming the fetus. However, the mechanism of STW remains unclear.

AIM OF STUDY

To study the mechanism and potential benefit of STW in pregnant mice with hydrocortisone and mifepristone-induced threatened abortion.

MATERIALS AND METHODS

The STW compounds were identified using gas chromatography-mass spectrometry analysis. STW-H, STW-M, or STW-L was separately given 3 mg/ml, 1.5 mg/ml and 0.75 mg/ml STW in the morning, and 2 mg/ml hydrocortisone in the afternoon from gestation day (D) 1-9 and once with 0.4 mg/kg mifepristone on D10. Didroxyprogesterone (0.1 mg/ml) and equal dose pure water were used to replace STW in didroxyprogesterone (DYD) group and model group respectively. The control group used pure water to replace STW, hydrocortisone, and mifepristone. We performed morphological and histological analyses of the maternal-fetal interface on day 10.

RESULTS

The embryo loss rate in the STW-H and DYD groups was lower than that in the model group. Hematoxylin and eosin (HE) staining suggested that the morphology of maternal-fetal interface was improved in the STW-H and DYD groups. Immunohistochemical (IHC), Quantitative Reverse Transcription Polymerase Chain Reactionstaining (qRT-PCR), and Western blot (WB) results indicated that HIF-1α expression in the maternal-fetal interface of the STW-H and DYD groups was higher than that in model group. The activities of HK, PKM, LDH and the concentration of lactic acid in the STW-H and DYD groups were higher than those in model group. Furthermore, the protein and mRNA levels of HK2, PKM2, LDHA, MCT4, and GPR81 were higher in the STW-H and DYD groups than those in the model group.

CONCLUSIONS

STW can reduce the pregnancy loss rate by regulating the glycolysis balance at the maternal-fetal interface of kidney deficiency threatened abortion model mice.

Prevention of Pregnancy Loss: Combining Progestogen Treatment and Psychological Support

Pregnancy loss can be defined as a loss before either 20 or 24 weeks of gestation (based on the first day of the last menstrual period) or the loss of an embryo or fetus less than 400 g in weight if the gestation age is unknown. Approximately 23 million pregnancy losses occur worldwide every year, equating to 15-20% of all clinically recognized pregnancies. A pregnancy loss is usually associated with physical consequences, such as early pregnancy bleeding ranging in severity from spotting to hemorrhage. However, it can also be associated with profound psychological distress, which can be felt by both partners and may include feelings of denial, shock, anxiety, depression, post-traumatic stress disorder, and suicide. Progesterone plays a key part in the maintenance of a pregnancy, and progesterone supplementation has been assessed as a preventative measure in patients at increased risk of experiencing a pregnancy loss. The primary objective of this piece is to assess the evidence for various progestogen formulations in the treatment of threatened and recurrent pregnancy loss, postulating that an optimal treatment plan would preferably include a validated psychological support tool as an adjunct to appropriate pharmacological treatment.

GRADE Use in Evidence Syntheses Published in High-Impact-Factor Gynecology and Obstetrics Journals: A Methodological Survey

Objective: To identify and describe the certainty of evidence of gynecology and obstetrics systematic reviews (SRs) using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Method: Database searches of SRs using GRADE, published between 1 January 2016 to 31 December 2020, in the 10 "gynecology and obstetrics" journals with the highest impact factor, according to the Journal Citation Report 2019. Selected studies included those SRs using the GRADE approach, used to determine the certainty of evidence. Results: Out of 952 SRs, ninety-six SRs of randomized control trials (RCTs) and/or nonrandomized studies (NRSs) used GRADE. Sixty-seven SRs (7.04%) rated the certainty of evidence for specific outcomes. In total, we identified 946 certainty of evidence outcome ratings (n = 614 RCT ratings), ranging from very-low (42.28%) to low (28.44%), moderate (17.65%), and high (11.63%). High and very low certainty of evidence ratings accounted for 2.16% and 71.60% in the SRs of NRSs, respectively, compared with 16.78% and 26.55% in the SRs of RCTs. In the SRs of RCTs and NRSs, certainty of evidence was mainly downgraded due to imprecision and bias risks. Conclusions: More attention needs to be paid to strengthening GRADE acceptance and building knowledge of GRADE methods in gynecology and obstetrics evidence synthesis.

Progesterone: A Steroid with Wide Range of Effects in Physiology as Well as Human Medicine

Progesterone is a steroid hormone traditionally linked with female fertility and pregnancy. In current reproductive medicine, progesterone and its analogues play crucial roles. While the discovery of its effects has a long history, over recent decades, various novel actions of this interesting steroid have been documented, of which its neuro- and immunoprotective activities are the most widely discussed. Discoveries of the novel biological activities of progesterone have also driven research and development in the field of progesterone analogues used in human medicine. Progestogen treatment has traditionally and predominately been used in maintaining pregnancy, the prevention of preterm labor, various gynecological pathologies, and in lowering the negative effects of menopause. However, there are also various other medical fields where progesterone and its analogues could find application in the future. The aim of this work is to show the mechanisms of action of progesterone and its metabolites, the physiological and pharmacological actions of progesterone and its synthetic analogues in human medicine, as well as the impacts of its production and use on the environment.

Prediction of miscarriage in first trimester by serum estradiol, progesterone and β-human chorionic gonadotropin within 9 weeks of gestation

Purpose

To predict miscarriage outcome within 12 weeks of gestational age by evaluating values of serum estradiol, progesterone and β-human chorionic gonadotropin (β-HCG) within 9 weeks of gestation.

Methods

One hundred sixty-five women with singleton pregnancies were retrospectively studied. Estradiol, progesterone and β-HCG levels were measured at 5–6 weeks of gestation and the measurements were repeated at 7–9 weeks. According to pregnancy outcome at 12 weeks of gestation, 71 cases were categorized into miscarriage group, and 94 cases into group of normal pregnancy. Each group was further divided into 5–6 and 7–9 weeks of gestation sub-group. Predictive values of estradiol, progesterone and β- HCG levels at 5–6 weeks and 7–9 weeks of gestation were analyzed with receiver operating characteristic (ROC) curves and logistic regression.

Results

Serum levels of estradiol at 7–9 weeks identified miscarriage with an area under the ROC curve (AUC) of 0.866 (95% CI 0. 793 ~ 0.938, P = 0.000), diagnostic cutoff value of 576 pg/ml, sensitivity of 0.804, and specificity of 0.829 respectively at the optimal threshold, according to Youden index. Progesterone levels at 7–9 weeks were with AUC of 0.766 (95% CI 0. 672 ~ 0.861, P = 0.000), cutoff value of 15.27 ng/ml, sensitivity of 0.921, and specificity of 0.558, respectively; Estradiol at 5–6 weeks were with AUC of 0.709 (95% CI 0. 616 ~ 0.801, P < 0.001), the diagnostic cutoff value of 320 pg/ml, sensitivity of 0.800, and specificity of 0.574, respectively.

The performance of the dual markers of estradiol and progesterone analysis (AUC 0.871, CI 0.793–0.950), three-markers analysis (AUC 0.869, CI 0.759–0.980)were slightly better than the single marker at 7-9 weeks. β-HCG or progesterone provide additional utility of estradiol prediction at 5–6 weeks with AUC 0.770 (0.672–0.869) for β-HCG and estradiol, AUC0.768(CI 0.670–0.866) for β-HCG, estradiol and progesterone and AUC 0.739 (CI 0.651–0.827) for progesterone and estradiol.

Conclusions

Low serum levels such as dual of estradiol and progesterone or estradiol alone at 7–9 weeks, β-HCG or progesterone combing estradiol at 5–6 weeks of gestation can be used better to predict miscarriage in first trimester.

Pregnancy-related complications and perinatal outcomes following progesterone supplementation before 20 weeks of pregnancy in spontaneously achieved singleton pregnancies: a systematic review and meta-analysis

BACKGROUND

Progesterone supplementation is widely performed in women with threatened miscarriage or a history of recurrent miscarriage; however, the effects of early progesterone supplementation on pregnancy-related complications and perinatal outcomes in later gestational weeks remain unknown.

METHODS

Ovid MEDLINE, the Cochrane Library, Embase and ClinicalTrials.gov were searched until April 3rd, 2021. Randomized controlled trials regarding spontaneously achieved singleton pregnancies who were treated with progestogen before 20 weeks of pregnancy and were compared with those women in unexposed control groups were selected for inclusion. We performed pairwise meta-analyses with the random-effects model. The risk of bias was assessed according to the Cochrane Collaboration tool. The primary outcomes included preeclampsia (PE), and gestational diabetes mellitus (GDM), with the results presented as odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

We identified nine eligible studies involving 6439 participants. The pooled OR of subsequent PE following early progestogen supplementation was 0.64 (95% CI 0.42-0.98, moderate quality of evidence). A lower OR for PE was observed in the progestogen group when the subgroup analysis was performed in the vaginal subgroup (OR 0.62, 95%CI 0.40-0.96). There was insufficient evidence of a difference in the rate of GDM between pregnant women with early progestogen supplementation and unexposed pregnant women (OR 1.02, 95% CI 0.79-1.32, low quality of evidence). The pooled OR of low birth weight (LBW) following oral dydrogesterone was 0.57 (95% CI 0.34-0.95, moderate quality of evidence). The results were affected by a single study and the total sample size of enrolled women did not reach the required information size.

CONCLUSION

Use of vaginal micronized progesterone (Utrogestan) in spontaneously achieved singleton pregnancies with threatened miscarriage before 20 weeks of pregnancy may reduce the risk of PE in later gestational weeks. Among spontaneously achieved singleton pregnancies with threatened miscarriage or a history of recurrent miscarriage, use of oral dydrogesterone before 20 weeks of pregnancy may result in a lower risk of LBW in later gestational weeks. However, the available data were not sufficient to reach definitive conclusions, which highlighted the need for future studies.

Real-world pharmacological treatment patterns of patients with threatened miscarriage in China from 2014 to 2020: A cross-sectional analysis

WHAT IS KNOWN AND OBJECTIVE

Approximately half of the patients with threatened miscarriage suffer an abortion, and consistent medication therapy to prevent threatened miscarriage is lacking. Our goal was to investigate the real-world pharmacological treatment patterns of patients with threatened miscarriage in China, with a focus on the trend and rationality of progestogen use over the last 7 years.

METHODS

We performed a cross-sectional analysis of data from the Hospital Prescription Analysis Cooperation Project that is overseen by the Chinese Pharmaceutical Association. Information was extracted from prescriptions of outpatients with threatened miscarriage between January 2014 and December 2020. We quantified the types of medications using the first level anatomical therapeutic chemical (ATC) classification code and the frequency of use of medicines classified as category X by the United States Food and Drug Administration (FDA). We also calculated the prevalence of the most frequently used progestogens by assessing prescription rates, determined the sum of the defined daily doses (DDDs) and defined daily cost (DDC) and evaluated the rationality of progestogens according to drug labels and guidelines.

RESULTS AND DISCUSSION

Of the 91,464 patients included in this study, 69.4% were from the eastern region, 92.5% were from tertiary hospitals, and 72.9% were between 25 and 34 years old. The average number of medications per patient was 1.4. The following types of medicines were the most prevalent: "genitourinary system and sex hormones" (90.7%), "alimentary tract and metabolism" (10.8%) and "blood and blood-forming organs" (9.9%). Progestogens were prescribed for 81,080 patients (88.6%), among which oral progesterone (39.7%) was the most commonly used, followed by oral dydrogesterone (34.4%), progesterone injection (26.0%), oral allylestrenol (0.7%) and progesterone gel (0.4%). In other words, 10,991 (12.0%) patients used more than one progestogen, and the top three combinations were oral dydrogesterone plus progesterone injection (5.6%), oral progesterone plus progesterone injection (4.7%) and oral dydrogesterone plus oral progesterone (1.1%). The prescription rate of dydrogesterone increased gradually, whereas that of progesterone, especially progesterone injection, obviously decreased. Among 34,760 prescriptions of progestogens with complete usage information, the primary errors of progestogen use were "low frequency" (18.4%), "high single dose" (15.9%) and "low single dose" (11.3%). In addition, 137 prescriptions were identified with drug-progestogen interactions, and 61 were identified with contraindications for progestogens. A total of 4.5% of prescriptions included FDA category X medicines.

WHAT IS NEW AND CONCLUSION

Our findings are the first to provide information on medication use in patients with threatened miscarriage over the last seven years in China. Medicines targeting the "genitourinary system and sex hormones," especially progestogens, were the most commonly prescribed medications, among which dydrogesterone was the most prevalent. However, it is remarkable that the use of progestogens for the treatment of threatened abortion is still controversial; thus, high-quality large sample studies are still required, especially among Chinese patients. Since usage errors in progestogen records and exposure to category X medicines were common, more efforts are needed to guarantee the safety and rationality of medicines used in pregnant women.

Use of oral progestogen in women with threatened miscarriage in the first trimester: a randomized double-blind controlled trial

STUDY QUESTION

Will use of oral progestogen in women with threatened miscarriage in the first trimester reduce the miscarriage rate when compared with placebo?

SUMMARY ANSWER

Use of oral progestogen in women with threatened miscarriage in the first trimester did not reduce miscarriage before 20 weeks when compared with placebo.

WHAT IS KNOWN ALREADY

Miscarriage is a common complication of pregnancy and occurs in 15-20% of clinically recognized pregnancies. Use of vaginal progestogens is not effective in reducing miscarriage but there is still no good evidence to support use of oral progestogen for the treatment of threatened miscarriage.

STUDY DESIGN, SIZE, DURATION

This was a randomized double-blind controlled trial. A total of 406 women presenting with threatened miscarriage in the first trimester were recruited from 30 March 2016 to May 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women attending Early Pregnancy Assessment Clinics because of vaginal bleeding during the first trimester were recruited and randomly assigned to use dydrogesterone 40 mg orally, followed by 10 mg orally three times a day or placebo until 12 completed weeks of gestation or 1 week after the bleeding stopped, whichever was later. The primary outcome was the miscarriage rate before 20 weeks of gestation.

MAIN RESULTS AND THE ROLE OF CHANCE

The two groups of women had comparable age, BMI, number of previous miscarriages, gestation and ultrasound findings at presentation. The miscarriage rate before 20 weeks of gestation was similar in both groups, being 12.8% (26/203) in the progestogen group and 14.3% (29/203) in the placebo group (relative risk 0.897, 95% CI 0.548-1.467; P = 0.772). The live birth rate was 81.3% in the progestogen group versus 83.3% in the placebo group (P = 0.697). No significant differences were found between the two groups in terms of obstetric outcomes and side effects.

LIMITATIONS, REASONS FOR CAUTION

The primary outcome was the miscarriage rate, rather than the live birth rate. Women were recruited from Early Pregnancy Assessment Clinics and those with heavy vaginal bleeding might be admitted into wards directly instead of attending Early Pregnancy Assessment Clinic. The severity of vaginal bleeding was subjectively graded by women themselves. The sample size was not adequate to demonstrate a smaller difference in the miscarriage rate between the progestogen and placebo groups. We did not exclude women with multiple pregnancy, which increased the risk of miscarriage although there was only one set of twin pregnancy in the placebo group.

WIDER IMPLICATIONS OF THE FINDINGS

Use of oral progestogen is not recommended in women with threatened miscarriage in the first trimester.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Health and Medical Research Fund, HKSAR (reference number 12132341). All authors declared no conflict of interest.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov with an identifier NCT02128685.

TRIAL REGISTRATION DATE

1 May 2014.

DATE OF FIRST PATIENT'S ENROLMENT

30 March 2016.

Current Resources for Evidence-Based Practice, March 2021

An extensive review of new resources to support the provision of evidence-based care for women and infants. The current column includes a discussion of men's experiences of pregnancy loss and commentaries on reviews focused on the effects of perineal massage on perineal trauma and air pollution and heat exposure on birth outcomes.