Progestogen for treating threatened miscarriage

Role of the vaginal microbiome in miscarriage: exploring the relationship

Miscarriage is a devastating pregnancy loss that affects many women worldwide. It is characterized as a spontaneous miscarriage that occurs before 20 weeks of gestation which affects more than 25% of pregnancies. While the causes of miscarriage are complex and multifactorial, recent research has suggested a potential role of the vaginal microbiota. The vaginal microbiome is a dynamic ecosystem of microbes that are essential for preserving vaginal health and avoiding infections. Vaginal dysbiosis has been accompanied with numerous adverse pregnancy complications, such as preterm birth. However, the effect of the vaginal microbiome in miscarriage is not fully understood. This review aims to investigate the link between vaginal microbiota and miscarriage. Also, we investigate the various mechanisms through which the vaginal microbiota may affect miscarriage. Additionally, we examine the implications of these research findings, specifically the possibility of vaginal microbiome screening and targeted interventions to prevent miscarriage.

Association between Pet Ownership and Threatened Abortion in Pregnant Women: The China Birth Cohort Study

Background: The aim of this study was to assess the association between pet ownership and threatened abortion (TA) in pregnant Chinese women. Materials and Methods: We enrolled pregnant women from 18 provinces and autonomous regions across China between November 2017 and December 2020. Participants were grouped based on the presence or absence of pet ownership. Pet owners were further sub-grouped based on the presence or absence of close contact with their pets. Pet species included cats, dogs, and both. Generalised linear mixed models, with province as a random effect, were used to estimate the associations between pet ownership and TA. Results: Pet ownership, whether or not one had close contact with pets, was associated with greater odds of TA (OR: 1.30, 95% CI: 1.21, 1.40). Keeping pet cats (OR: 1.24, 95% CI: 1.11, 1.40), dogs (OR: 1.29, 95% CI: 1.18, 1.41), or both cats and dogs (OR: 1.36, 95% CI: 1.04, 1.68) during pregnancy were all risk factors for TA. We observed significant group differences (p for difference < 0.05) in pre-pregnancy body mass index, education levels, and annual household income. Conclusions: Cat or dog ownership during pregnancy was associated with an increased risk of TA, especially among overweight, less educated, or lower-income participants.

Construction of machine learning tools to predict threatened miscarriage in the first trimester based on AEA, progesterone and β-hCG in China: a multicentre, observational, case-control study

Background

Endocannabinoid anandamide (AEA), progesterone (P4) and β-human chorionic gonadotrophin (β-hCG) are associated with the threatened miscarriage in the early stage. However, no study has investigated whether combing these three hormones could predict threatened miscarriage. Thus, we aim to establish machine learning models utilizing these three hormones to predict threatened miscarriage risk.

Methods

This is a multicentre, observational, case-control study involving 215 pregnant women. We recruited 119 normal pregnant women and 96 threatened miscarriage pregnant women including 58 women with ongoing pregnancy and 38 women with inevitable miscarriage. P4 and β-hCG levels were detected by chemiluminescence immunoassay assay. The level of AEA was tested by ultra-high-performance liquid chromatography-tandem mass spectrometry. Six predictive machine learning models were established and evaluated by the confusion matrix, area under the receiver operating characteristic (ROC) curve (AUC), accuracy and precision.

Results

The median concentration of AEA was significantly lower in the healthy pregnant women group than that in the threatened miscarriage group, while the median concentration of P4 was significantly higher in the normal pregnancy group than that in the threatened miscarriage group. Only the median level of P4 was significantly lower in the inevitable miscarriage group than that in the ongoing pregnancy group. Moreover, AEA is strongly positively correlated with threatened miscarriage, while P4 is negatively correlated with both threatened miscarriage and inevitable miscarriage. Interestingly, AEA and P4 are negatively correlated with each other. Among six models, logistic regression (LR), support vector machine (SVM) and multilayer perceptron (MLP) models obtained the AUC values of 0.75, 0.70 and 0.70, respectively; and their accuracy and precision were all above 0.60. Among these three models, the LR model showed the highest accuracy (0.65) and precision (0.70) to predict threatened miscarriage.

Conclusions

The LR model showed the highest overall predictive power, thus machine learning combined with the level of AEA, P4 and β-hCG might be a new approach to predict the threatened miscarriage risk in the near feature.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05025-y.

A Comparative, Randomized Control Trial in Patients of Per Vaginal Bleeding Comparing Efficacy of Oral Dydrogesterone Versus Vaginal Progesterone in Successful Pregnancy Outcome for Patients with Recurrent Pregnancy Loss

Background

Progesterone is essential for the maintenance of a healthy pregnancy. Any defect in the secretion of human chorionic gonadotropin or progesterone is associated with a significantly increased risk of first-trimester abortion. Progesterone is frequently prescribed to patients presenting with per vaginal (PV) bleeding in early pregnancy and a history of recurrent pregnancy loss.

Methods

Pregnant women up to 12 weeks of gestation with a history of more than two early pregnancy losses and presenting with vaginal bleeding were included in this study. All subjects were randomized to receive either vaginal progesterone 600 mg/day or oral dydrogesterone 30 mg/day. A detailed history-including menstrual history, previous pregnancies, previous miscarriages, and other risk factors-was obtained. The mean time required for the cessation of PV bleeding and continuation of pregnancy up to 24 weeks and till term was compared.

Results

A total of 200 patients were randomized to vaginal progesterone 600 mg/day (n = 100) or oral dydrogesterone 30 mg/day (n = 100). While 74 patients had two miscarriages in the progesterone group, 68 patients had two miscarriages in the dydrogesterone group. The time required for complete cessation of bleeding was significantly lesser among patients who received oral dydrogesterone compared to those who received intravaginal progesterone (53.90 ± 9.09 vs. 94.60 ± 7.29 h, p < 0.0001). Numerically higher number of patients receiving oral dydrogesterone had a successful continuation of pregnancy up to 24 weeks of gestation, as well as till full term compared to progesterone group (70 vs. 75).

Conclusion

Oral dydrogesterone is preferred over vaginal progesterone in patients presenting with vaginal bleeding during early pregnancy and a history of recurrent early pregnancy loss.

The Modified Bushen Antai Recipe Upregulates Estrogen and Progesterone Receptors at the Maternal-Fetal Interface in Pregnant Rats with Mifepristone-Induced Pregnancy Loss

Background

The modified Bushen Antai recipe (BSAT) is a centuries-old traditional Chinese medicine that we use in our center as a therapy against pregnancy loss. Our study aimed to explore the potential benefit and mechanism of BSAT in pregnant rats with mifepristone-induced pregnancy loss.

Materials and Methods

The signature compounds of the eight BSAT ingredients were analyzed by high-performance liquid chromatography (HPLC). The BSAT group (n = 8) was treated daily with 6.3 ml/kg BSAT from gestation day (D) 0.5 to 10.5 and once with 1.25 mg/kg mifepristone on D 10.5. Normal saline replaced BSAT in the model group (n = 8), and both BSAT and mifepristone in the control group (n = 8). Morphological and histological analyses were performed on D 13.5.

Results

BSAT contains eight medicinal ingredients including Cuscuta chinensis and Dipsacus asperoides. The HPLC analysis detected the signature compounds of seven medicinal ingredients in the extract. Embryo resorption rate in the BSAT group was significantly lower than that in the model group, although the number of surviving embryos was similar between the two groups. Hematoxylin and eosin (HE) staining suggested that the maximum cross-sectional area of the placenta and the area ratio of the placental labyrinth in the BSAT group were higher than those in the model group. Immunohistochemical (IHC) staining indicated that the expression of ki67, estrogen receptor alpha (ERα), and progesterone receptor (PR) in the placental labyrinth of the BSAT group was higher than that of the model group. Furthermore, the protein levels of ERα, PR, phospho-Akt/Akt, and phospho-Erk1/2/Erk1/2 in the BSAT group were higher than those in the control group. The mRNA levels of ERα and PR in the BSAT group were higher than those in the control group.

Conclusions

BSAT may induce estrogen and progesterone receptors by phosphorylation via the classic Akt and Erk1/2 signaling pathways in the maternal-fetal interface of pregnant rats, thereby reducing the pregnancy loss rate and improving the live birth rate.

The randomised controlled trial of micronised progesterone and dydrogesterone (TRoMaD) for threatened miscarriage

There has not been conclusive evidence in literature on the efficacy of progestogen in the treatment of threatened miscarriage, although some studies showed benefits. In our centre, threatened miscarriage is treated with either micronised progesterone (MP) or dydrogesterone (DYD).

OBJECTIVE

The aim of this study is to compare clinical outcomes of miscarriage, extent of vaginal bleeding at follow-up and side effects between treatment groups.

STUDY DESIGN

This study was a prospective parallel-group, open-label, randomized controlled trial. 141 women presenting with threatened miscarriage were randomised to either MP or DYD of which 118 were included in the analysis. Baseline maternal demographics and serum progesterone levels were collected at presentation. Post-treatment bleeding pattern and self-reported side effects were recorded at the follow-up visit (on day 4-10 of treatment). The occurrence of spontaneous miscarriage was ascertained at week 16 of gestation.

RESULTS

The population with miscarriage and resolution of bleeding were not statistically different between MP and DYD groups. A significantly higher percentage of women treated with MP reported drowsiness (p = 0.003). After stratification into low and high serum progesterone levels, a significantly higher miscarriage rate was found in the low progesterone group, regardless of treatment type.

CONCLUSION

In conclusion, extent of bleeding at day 4-10 and subsequent miscarriage rates were comparable between MP and DYD groups. However, fewer patients treated with DYD reported drowsiness and giddiness. The finding of significantly higher miscarriage rates in women with low progesterone levels despite treatment is an important factor to consider in counselling and prognosticating pregnancy outcomes.

Luteal phase support for documented failure of placental steroidogenesis: A case report

OBJECTIVE

To report a case of a habitual aborter that had a pregnancy reach near term and successfully delivered a viable female infant.

DESIGN

Report of a unique case of a G10P1 that was successfully able to maintain a pregnancy by maintaining serum levels of estradiol and progesterone at or above 200 pg/dL and 25 ng/dL respectively. This case provides a benchmark for exogenous support of estradiol and progesterone throughout pregnancy.

SETTING

A private advanced reproductive center.

PATIENT

39-year-old G10P1091 diagnosed to have antiphospholipid syndrome but continued to have continuous miscarriages despite accepted treatment. In addition, 8 products of conception were sent for cytogenetic testing and all were found to be normal.

INTERVENTIONS

Examination, laboratory studies, imaging, clinical judgment, and knowledge of previous treatment failures were used to guide the treatment of this patient. Fertility was achieved with continuous supplementation of progesterone, estrogen, LMW-heparin, and prednisone.

MAIN OUTCOME MEASURE

Delivery of viable infant.

RESULTS

This advanced reproductive age woman had three subsequent pregnancies. While compliant with our prescribed protocol, the patient successfully carried two pregnancies to viability.

CONCLUSION

Clinicians should be alert to the possibility of a luteal phase defect when a patient presents with recurrent fertility problems and multiple spontaneous abortions.

MULTIPLE PREGNANCY, ANTENATAL CARE PROBLEMS AND THEIR SOLUTIONS RESULTS

Aim of the work. The aim of our study is to summarize the course of pregnancy and delivery in multiple pregnancies in modern conditions. Materials and methods. The analysis of the pregnancy course, labor and perinatal outcomes was carried out in 182 women with diochorionic and 86 patients with monochorionic twins and 40 women with a singleton pregnancy. Multiple pregnancies were proved to be a monochorionic (MH) and diochorionic (DH) that is a high risk factor for perinatal complications. The research included clinical and laboratory examination metods, study of hormonal function of fetoplacental complex (FPC), transvaginal ultrasound examination. Statistical processing of data was carried out using the package of applied programs Microsoft Office Excel 2010 and StatSoft Statistica 6.1. Results and discussion. In the analysis of pregnancy the abortion threat was detected in 51 (59.3%) women with monochorionic and 34 (62%) women with diochorionic twins. Preeclampsia during pregnancy complicated in 26 (30.2%) and 43 (23.6%) patients, with monochorionic and diochorionic placentation type, respectively. A frequent complication of both the MH and DH twins was anemia, which was found in more than half of the surveyed (56.9 and 51%, respectively). Delivery in the case of multiple pregnancies is also much more complicated and is terminated surgically three times more often than in singleton births. The most frequent indications for operative delivery were first breech fetus, fetal distress during pregnancy and childbirth, FGR, severe preeclampsia, premature detachment of normally situated placenta, anomalies of labor activity. These perinatal losses were equally observed both after cesarean section and after spontaneous labor and amounted to 4% at monochorionic and 1.7% at diochorionic twins. The frequency dependence of identified lesions at pregnancy with twins was established by chorionic. Careful observation of the patients with multiple pregnancies in the antenatal period, the prevention of the most frequent complications, ultrasound monitoring of early pregnancy allows a differentiated approach to the management of pregnancy and childbirth, helping to reduce perinatal morbidity and mortality. Conclusions. Multiple pregnancies occur with a large number of complications compared with singletons. Thus, the increase of frequency of multiple pregnancy influences the obstetric and perinatal indicators, pushing this issue in a number of the most pressing issues of modern obstetrics and perinatology.

A randomized double-blind controlled trial of the use of dydrogesterone in women with threatened miscarriage in the first trimester: study protocol for a randomized controlled trial

Background

Miscarriage is a common complication of pregnancy occurring in 15–20 % of all clinically recognized pregnancies. Currently, there is still no good scientific evidence to support the routine use of progestogens for the treatment of threatened miscarriage because the existing studies were not large enough to show a significant difference and some of them were not randomized or double-blind.

Methods

This is a double-blind, randomized controlled trial. A total of 400 patients presenting with first-trimester threatened miscarriage will be enrolled. They will be randomized to take dydrogesterone 40 mg per os, followed by 10 mg per os three times a day or placebo until twelve completed weeks of gestation or 1 week after the bleeding has stopped, whichever is longer. The primary outcome is the percentage of miscarriage before 20 weeks of gestation.

Discussion

We postulate that the dydrogesterone therapy will significantly reduce the risk of miscarriage in women with threatened miscarriage.

Trial registration

This study is registered at ClinicalTrials.gov, NCT02128685. Registered on 29 April 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1509-8) contains supplementary material, which is available to authorized users.

Prevention of Hypertensive Disorders of Pregnancy: a Novel Application of the Polypill Concept

Nearly all of the annual 287,000 global maternal deaths are preventable. Hypertensive disorders of pregnancy (HDP) are among the major causes. A novel fixed-dose combination pill or polypill to prevent cardiovascular disease is a promising strategy for prevention of HDP. The aim of this study was to identify eligible candidates for a polypill for the prevention of HDP. A comprehensive review of systematic reviews on drug and dietary interventions to prevent HDP was conducted. Interventions were evaluated based on efficacy, dose, route of administration, and side effects. Fourteen interventions were assessed. Low-dose aspirin and calcium were identified as candidates for a polypill, with risk reduction estimations for pregnancy-induced hypertension and preeclampsia ranging between 10 and 62 %, depending on patient population characteristics including a priori risk, and gestation age at start of intervention. Their effect may be augmented through the addition of vitamin D, vitamin B12, and folic acid. The effect and optimal composition needs to be evaluated in future trials. Given the persistent burden of maternal and perinatal mortality associated with HDP, prevention of these disorders is key-especially in low-resource settings. The polypill approach with a combination of aspirin, calcium, vitamin D, vitamin B12, and folic acid is a promising strategy to improve maternal and perinatal health outcomes.

Perinatal outcomes in singleton and twin ICSI pregnancies following hysteroscopic correction of partial intrauterine septa

PURPOSE

To investigate the perinatal outcomes of patients with clinical pregnancies from ICSI treatments who had previously undergone hysteroscopic surgery to correct partial intrauterine septa and compare them to outcomes of patients with no intrauterine anomalies.

METHOD

A retrospective observational analysis of 2024 ultrasound confirmed pregnancies from ICSI treatments performed between January 2005 and June 2012. The patients were grouped according to their intrauterine status, and sub-grouped according to the number of fetal hearts observed; singleton control (n=1128), twin control (n=566), singleton septum (n=217) and twin septum (n=113). The primary outcomes analyzed were miscarriage, preterm, very preterm, stillbirth, vanishing twin and live delivery rates, as well as low birth weight and very low birth weight rates.

RESULT(S)

The live birth rate (89,9 %) in the singleton control subgroup was non-significantly higher than the live birth rate (85,3 %) in the septum subgroup, with a RR of 1,05 (p=0,0583, 95 % CI 0,9943-1,1182) for live birth. In contrast the live birth rate (91,3 %) in twin control subgroup was significantly higher than the live birth rate (84,1 %) in the septum subgroup, with a RR 1,09 (p=0,0282, 95 % CI 0,9988-1,1819). Non-significantly, higher miscarriage and stillbirth rates were the main contributors to the reduced live birth rates. The singleton and twin septum subgroups also had higher rates of premature and very premature delivery and LBWs and vLBW, especially in the singleton septum subgroup.

CONCLUSION(S)

The hysteroscopic correction of intrauterine septa may not eliminate all risks for premature delivery.

Safety of Chinese herbal medicines during pregnancy

Miscarriage and infertility have long been public concerns due to the mental and physical suffering they bring to potential parents. There is a strong need for effective and affordable treatments. Chinese herbal medicines (CHMs) have been shown to be effective for preventing miscarriage and treating infertility; however, due to the limited knowledge of their pharmacological mechanisms and unknown potential toxicity, their use has been restricted. This paper reviews 24 clinical trials of CHMs to prevent miscarriage and treat infertility. Most of these studies did not meet the requirements of randomized controlled trials. Even when using quality assessments based on the Newcastle-Ottawa Scale to assess the quality of non-randomized studies, most studies did not meet the requirements. The reviewed papers were evaluated for maternal and embryonic adverse effects, including those in animal experiments. Slight maternal effects were noted, with some reports of severe toxic effects of CHMs for preventing miscarriage and severe adverse maternal effects of CHMs used for infertility. Owing to the poor quality of the randomized controlled clinical trials and the limited number of studies, it is not possible to draw a conclusion. From animal studies, for all three gestational periods, growth delay and congenital anomalies were the most commonly recorded adverse effects. However, baseline toxicological data and detailed mechanisms are still lacking. To gain a better understanding of the potential toxic effects of CHMs, additional high-quality randomized controlled trials should be conducted, and high-throughput in vitro screening method for baseline data should be considered.

HIV protease inhibitor use during pregnancy is associated with decreased progesterone levels, suggesting a potential mechanism contributing to fetal growth restriction

BACKGROUND

Protease inhibitor (PI)-based combination antiretroviral therapy (cART) is administered during pregnancy to prevent perinatal human immunodeficiency virus (HIV) transmission. However, PI use has been associated with adverse birth outcomes, including preterm delivery and small-for-gestational-age (SGA) births. The mechanisms underlying these outcomes are unknown. We hypothesized that PIs contribute to these adverse events by altering progesterone levels.

METHODS

PI effects on trophoblast progesterone production were assessed in vitro. A mouse pregnancy model was used to assess the impact of PI-based cART on pregnancy outcomes and progesterone levels in vivo. Progesterone levels were assessed in plasma specimens from 27 HIV-infected and 17 HIV-uninfected pregnant women.

RESULTS

PIs (ritonavir, lopinavir, and atazanavir) but not nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcriptase inhibitors reduced trophoblast progesterone production in vitro. In pregnant mice, PI-based cART but not dual-NRTI therapy was associated with significantly lower progesterone levels that directly correlated with fetal weight. Progesterone supplementation resulted in a significant improvement in fetal weight. We observed lower progesterone levels and smaller infants in HIV-infected women receiving PI-based cART, compared with the control group. In HIV-infected women, progesterone levels correlated significantly with birth weight percentile.

CONCLUSIONS

Our data suggest that PI use in pregnancy may lead to lower progesterone levels that could contribute to adverse birth outcomes.

Systematic Review of Chinese Medicine for Miscarriage during Early Pregnancy

Background. Miscarriage is a very common complication during early pregnancy. So far, clinical therapies have limitation in preventing the early pregnancy loss. Chinese Medicine, regarded as gentle, effective, and safe, has become popular and common as a complementary and alternative treatment for miscarriages. However, the evidence to support its therapeutic efficacy and safety is still very limited. Objectives and Methods. To summarize the clinical application of Chinese Medicine for pregnancy and provide scientific evidence on the efficacy and safety of Chinese medicines for miscarriage, we located all the relevant pieces of literature on the clinical applications of Chinese Medicine for miscarriage and worked out this systematic review. Results. 339,792 pieces of literature were identified, but no placebo was included and only few studies were selected for systematic review and conducted for meta-analysis. A combination of Chinese medicines and Western medicines was more effective than Chinese medicines alone. No specific safety problem was reported, but potential adverse events by certain medicines were identified. Conclusions. Studies vary considerably in design, interventions, and outcome measures; therefore conclusive results remain elusive. Large scales of randomized controlled trials and more scientific evidences are still necessary to confirm the efficacy and safety of Chinese medicines during early pregnancy.

The immune privilege of testis and gravid uterus: same difference?

The fetus in the gravid uterus and the developing spermatogenic cells in the adult testis both comprise special challenges for the host immune system. Protection of the neoantigens of the fetus and male germ cells from immune attack, defined as immune privilege, is fundamental for the propagation of species. Immune privilege is not simply the absence of leukocytes, but involves immune and non-immune cells acting synergistically together at multiple levels to create a unique tolerogenic environment. A number of the pathways are shared by the testis and gravid uterus. Amongst them steroid hormones, namely testosterone in the male and progesterone in the female, seem to function as key molecules that govern the local production of immunoregulatory factors which finally control the overall immune environment.

Combined oestrogen and progesterone for preventing miscarriage

BACKGROUND

Historically, oestrogen and progesterone were each commonly used to save threatened pregnancies. In the 1940s it was postulated that their combined use would be synergistic and thereby led to the rationale of combined therapy for women who risked miscarriage.

OBJECTIVES

To determine the efficacy and safety of combined oestrogen and progesterone therapy to prevent miscarriage.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (23 June 2013) CENTRAL (OVID) (The Cochrane Library 2013, Issue 6 of 12), MEDLINE (OVID) (1946 to June Week 2 2013), OLDMEDLINE (1946 to 1965), Embase (1974 to Week 25 2013), Embase Classic (1947 to 1973), CINAHL (1994 to 23 June 2013) and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials that assessed the effectiveness of combined oestrogen and progesterone for preventing miscarriage. We included one stratified randomised trial and one quasi-randomised trials. Cluster-randomised trials were eligible for inclusion but none were identified. We excluded studies published only as abstracts.We included studies that compared oestrogen and progesterone versus placebo or no intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors extracted data. Data were checked for accuracy.

MAIN RESULTS

Two trials (281 pregnancies and 282 fetuses) met our inclusion criteria. However, the two trials had significant clinical and methodological heterogeneity such that a meta-analysis combining trial data was considered inappropriate.One trial (involving 161 pregnancies) was based on women with a history of diabetes. It showed no statistically significant difference between using combined oestrogen and progestogen and using placebo for all our proposed primary outcomes, namely, miscarriage (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.32 to 2.80), perinatal death (RR 0.94, 95% CI 0.53 to 1.69) and preterm birth (less than 34 weeks of gestation) (RR 0.91, 95% CI 0.80 to 1.04). In terms of this review's secondary outcomes, use of combined oestrogen and progestogen was associated with an increased risk of maternal cancer in the reproductive system (RR 6.65, 95% CI 1.56 to 28.29). However, for the outcome of cancer other than that of the reproductive system in mothers, there was no difference between groups. Similarly, there were no differences between the combined oestrogen and progestogen group versus placebo for other secondary outcomes reported: low birthweight of less than 2500 g, genital abnormalities in the offspring, abnormalities other than genital tract in the offspring, cancer in the reproductive system in the offspring, or cancer other than of the reproductive system in the offspring.The second study was based on pregnant women who had undergone in-vitro fertilisation (IVF). This study showed no difference in the rate of miscarriage between the combined oestrogen and progesterone group and the no treatment group (RR 0.66, 95% CI 0.23 to 1.85). The study did not report on this review's other primary outcomes (perinatal death or rates of preterm birth), nor on any of our proposed secondary outcomes.

AUTHORS' CONCLUSIONS

There is an insufficient evidence from randomised controlled trials to assess the use of combined oestrogen and progesterone for preventing miscarriages. We strongly recommend further research in this area.

Chinese herbal medicines for threatened miscarriage

BACKGROUND

Threatened miscarriage occurs in 10% to 15% of all pregnancies. Vaginal spotting or bleeding during early gestation is common, with nearly half of those pregnancies resulting in pregnancy loss. To date, there is no effective preventive treatment for threatened miscarriage. Chinese herbal medicines have been widely used in Asian countries for centuries and have become a popular alternative to Western medicines in recent years. Many studies claim to show that they can prevent miscarriage. However, there has been no systematic evaluation of the effectiveness of Chinese herbal medicines for threatened miscarriage.

OBJECTIVES

To review the therapeutic effects of Chinese herbal medicines for the treatment of threatened miscarriage.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2012), Chinese Biomedical Database (1978 to 31 January 2012), China Journal Net (1915 to 31 January 2012), China National Knowledge Infrastructure (1915 to 31 January 2012), WanFang Database (1980 to 31 January 2012), Chinese Clinical Trial Registry (31 January 2012), EMBASE (1980 to 31 January 2012), CINAHL (31 January 2012), PubMed (1980 to 31 January 2012), Wiley InterScience (1966 to 31 January 2012), International Clinical Trials Registry Platform (31 January 2012) and reference lists of retrieved studies. We also contacted organisations, individual experts working in the field, and medicinal herb manufacturers.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials that compared Chinese herbal medicines (alone or combined with other pharmaceuticals) with placebo, no treatment (including bed rest), or other pharmaceuticals as treatments for threatened miscarriage.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all the studies for inclusion in the review, assessed risk of bias and extracted the data. Data were checked for accuracy.

MAIN RESULTS

In total, we included 44 randomised clinical trials with 5100 participants in the review.We did not identify any trials which used placebo or no treatment (including bed rest) as a control.The rate of effectiveness (continuation of pregnancy after 28 weeks of gestation) was not significantly different between the Chinese herbal medicines alone group compared with the group of women receiving Western medicines alone (average risk ratio (RR) 1.23; 95% confidence interval (CI) 0.96 to 1.57; one trial, 60 women).Chinese herbal medicines combined with Western medicines were more effective than Western medicines alone to continue the pregnancy beyond 28 weeks of gestation (average RR 1.28; 95% CI 1.18 to 1.38; five trials, 550 women).

AUTHORS' CONCLUSIONS

There was insufficient evidence to assess the effectiveness of Chinese herbal medicines alone for treating threatened miscarriage.A combination of Chinese herbal and Western medicines was more effective than Western medicines alone for treating threatened miscarriage. However, the quality of the included studies was poor. More high quality studies are necessary to further evaluate the effectiveness of Chinese herbal medicines for threatened miscarriage.