Recurrent miscarriage: Are three miscarriages one too many? Analysis of a Scottish population-based database of 151,021 pregnancies

Recurrent Early Pregnancy Loss and Congenital Thrombophilia: A Prospective Study

Background/Objectives: This study aims to investigate the role of congenital single nucleotide thrombophilia in young females with early recurrent pregnancy loss (RPL). Methods: We studied 120 pregnant females with RPL and 80 matched females as a control with no RPL. Females were aged ≤ 35 years, had at least two consecutive first-trimester RPLs, and the acquired cause of RPL was excluded. A matched control group of 80 pregnant women with no RPL was studied. Coagulation tests included prothrombin time (PT), partial thromboplastin time (PTT), thrombin time (TT), a Factor XIII functional assay, and detecting IgM and IgG anti-beta2-Glycoprotein I (β2GPI) antibodies by an ELISA. The DNA samples were tested for Factor V Leiden, Factor II G20210A, Methylenetetrahydrofolate reductase (MTHFR C677T, A1298C), FXIII V34L, plasminogen activator inhibitor-1 (PAI-1) 4G/5G, endothelial protein C receptor (EPCR) A4600G, and endothelial protein C receptor (EPCR) G4678C. Results: Of the single nucleotide gene mutations investigated, the most relevant mutations were MTHFR C677T, MTHFR A1298C, heterozygous FXIII Val34Leu, and heterozygous FXIII 1694 C>T. Each of them conferred a statistically significant effect. There was a statistically significant protective role for the endothelial protein C receptor (EPCR) A2/A2, wild FXIII Val34Leu, and heterozygousFXIII1694 C>T. Conclusions: Our findings suggest the important role of congenital single nucleotide thrombophilia mutations in young Middle Eastern women with early RPL, particularly MTHFR mutations and FXIII Val34Leu. We found a protective effect of EPCR A2/A2, wild FXIIIVal34Leu, and heterozygous FXIII1694 C>T. We recommend additional studies to explore detrimental factors and protective factors.

Adverse Perinatal Outcomes Among Teenage Mothers Delivering at a Tertiary Referral Hospital in Southwestern Uganda: Prevalence and Associated Factors

INTRODUCTION

Each year, millions of teenagers in low-resource areas experience unintended pregnancies, many of which result in childbirth. These pregnancies often carry an increased risk of negative perinatal outcomes.

OBJECTIVES

The study determined the prevalence and factors associated with adverse perinatal outcomes among teenagers delivering at a tertiary referral hospital in southwestern Uganda.

METHODS

This cross-sectional study was carried out in the Department of Obstetrics and Gynecology. We consecutively included all teenagers (13-19 years) in the postnatal ward who delivered. Descriptive statistics were used to summarize demographic and outcome data, and multivariable logistic regression analysis was used to identify factors associated with adverse perinatal outcomes.

RESULTS

Overall, 327 participants were enrolled. The mean age was 18.4 (SD 1.1) years, while the mean number of antenatal care (ANC) visits attended was 4.6 (SD 1.9). Less than half delivered by cesarean 136 (41.6%) and 16 (4.9%) were HIV seropositive. Approximately 140 (42.8%) participants had adverse perinatal outcomes, including neonatal death (7, 2.1%), APGAR score at five minutes <7 (44, 13.5%), or low birth weight <2.5 kg (52, 15.9%). ANC attendance was mildly protective against adverse perinatal outcomes (aOR 0.91 (95% CI 1.14, 3.01), p=0.03). Feeling indifferent toward the pregnancy was associated with increased odds of one or more adverse perinatal outcomes compared to feeling happy about the pregnancy (aOR 3.39 (95% CI 1.11, 10.37), p=0.02). Participants with a history of prior miscarriage had increased odds of adverse perinatal outcomes (aOR 9.03 (95% CI 2.45, 25.53), p=0.04).

CONCLUSIONS

Nearly half of teenagers experienced adverse perinatal outcomes, and a history of prior miscarriage was a significant risk factor for adverse perinatal outcomes, while ANC was protective. Prospective cohort studies to explore the newborn and child developmental outcomes among children born to teenage mothers are also recommended.

Identification and analysis of biomarkers associated with oxidative stress and ferroptosis in recurrent miscarriage

Recurrent miscarriage (RM) has a huge impact on women. Both oxidative stress and ferroptosis play an important role in the pathogenesis of RM. Hence, it was vital to screen the ferroptosis oxidation-related biomarkers for the diagnosis and treatment of RM. We introduced transcript data to screen out differentially expressed genes (DEGs) in RM. Ferroptosis oxidation-related differentially expressed genes were obtained by overlapping DEGs and oxidative stress related genes with correlations >0.9 with ferroptosis-related genes. Least Absolute Shrinkage and Selectionator operator regression and support vector machine based recursive feature elimination algorithm were implemented to screen feature genes. The biomarkers associated with ferroptosis oxidation were screened via receiver operating characteristic curve analysis. We finally analyzed the competing endogenous RNAs regulatory network and potential drugs of biomarkers. We identified 1047 DEGs in RM. Then, 9 ferroptosis oxidation-related differentially expressed genes were obtained via venn diagram. Subsequently, 8 feature genes (PTPN6, GJA1, HMOX1, CPT1A, CREB3L1, SNCA, EPAS1, and TGM2) were identified via machine learning. Moreover, 4 biomarkers associated with ferroptosis oxidation, including PTPN6, GJA1, CPT1A, and CREB3L1, were screened via receiver operating characteristic curve analysis. We constructed the '227 long noncoding RNAs-4 mRNAs-36 microRNAs' network, in which hsa-miR-635 was associated with CREB3L1 and PTPN6. There were 11 drugs with therapeutic potential on 3 biomarkers associated with ferroptosis oxidation. We also observed higher expression of CPT1A and CREB3L1 in RM group compared to the healthy control group by quantitative real-time reverse transcription polymerase chain reaction. Overall, we obtained 4 biomarkers (PTPN6, GJA1, CPT1A, and CREB3L1) associated with ferroptosis and oxidative stress, which laid a theoretical foundation for the diagnosis and treatment of RM.

Adverse outcomes in subsequent pregnancies in women with history of recurrent spontaneous abortion: A meta-analysis

OBJECTIVE

This study aimed to investigate the association between a history of recurrent spontaneous abortion (RSA) and adverse outcomes in women with spontaneous conception.

METHODS

A search strategy from the inception to March 3, 2023 was run in PubMed, Embase, Cochrane Library, and Web of Science databases. The odds ratio (OR), and the 95% confidence interval (CI) or point estimation were used as the evaluation indexes. Each outcome measure tested was assessed for heterogeneity using the Cochran Q test. Sensitivity analyses were performed to test the credibility of the meta-analysis results.

RESULTS

Fifteen studies involving 1 475 389 pregnant women were included. A history of RSA was associated with gestational diabetes (OR: 2.21, 95% CI: 1.70-2.87, p < 0.001), preeclampsia (OR: 2.06, 95% CI: 1.49-2.86, p < 0.001), placenta previa (OR: 1.82, 95% CI: 1.09-3.02, p = 0.021), placental abruption (OR: 1.67, 95% CI: 1.36-2.06, p < 0.001), miscarriage (OR: 6.37, 95% CI: 3.83-10.57, p < 0.001), preterm birth (OR: 1.80, 95% CI: 1.36-2.37, p < 0.001), cesarean section (OR: 1.47, 95% CI: (1.13-1.91, p = 0.004), perinatal death (OR: 2.24, 95% CI: 1.39-3.60, p = 0.001), and neonatal intensive care unit admission (OR: 1.39, 95% CI: 1.01-1.92, p = 0.047). However, the associations of a history of RSA with gestational hypertension, small for gestational age, fetal anomalies, fetal growth restriction, and postpartum hemorrhage were not observed.

CONCLUSION

This meta-analysis indicates a history of RSA was associated with increased risks of several adverse outcomes in pregnant women with spontaneous conception.

Subsequent pregnancy outcomes after second trimester miscarriage or termination for medical/fetal reason: A systematic review and meta-analysis of observational studies

INTRODUCTION

Women with a prior stillbirth or a history of recurrent first trimester miscarriages are at increased risk of adverse pregnancy outcomes. However, little is known about the impact of a second trimester pregnancy loss on subsequent pregnancy outcome. This review investigated if second trimester miscarriage or termination for medical reason or fetal anomaly (TFMR/TOPFA) is associated with future adverse pregnancy outcomes.

MATERIAL AND METHODS

A systematic review of observational studies was conducted. Eligible studies included women with a history of a second trimester miscarriage or termination for medical reasons and their pregnancy outcomes in the subsequent pregnancy. Where comparative studies were identified, studies which compared subsequent pregnancy outcomes for women with and without a history of second trimester loss or TFMR/TOPFA were included. The primary outcome was livebirth, and secondary outcomes included: miscarriage (first and second trimester), termination of pregnancy, fetal growth restriction, cesarean section, preterm birth, pre-eclampsia, antepartum hemorrhage, stillbirth and neonatal death. Studies were excluded if exposure was nonmedical termination or if related to twins or higher multiple pregnancies. Electronic searches were conducted using the online databases (MEDLINE, Embase, PubMed and The Cochrane Library) and searches were last updated on June 16, 2023. Risk of bias was assessed using the Newcastle-Ottawa scale. Where possible, meta-analysis was undertaken. PROSPERO registration: CRD42023375033.

RESULTS

Ten studies were included, reporting on 12 004 subsequent pregnancies after a second trimester pregnancy miscarriage. No studies were found on outcomes after second trimester TFMR/TOPFA. Overall, available data were of "very low quality" using GRADE assessment. Meta-analysis of cohort studies generated estimated outcome frequencies for women with a previous second trimester loss as follows: live birth 81% (95% CI: 64-94), miscarriage 15% (95% CI: 4-30, preterm birth 13% [95% CI: 6-23]).The pooled odds ratio for preterm birth in subsequent pregnancy after second trimester loss in case-control studies was OR 4.52 (95% CI: 3.03-6.74).

CONCLUSIONS

Very low certainty evidence suggests there may be an increased risk of preterm birth in a subsequent pregnancy after a late miscarriage. However, evidence is limited. Larger, higher quality cohort studies are needed to investigate this potential association.

Predicting risk of subsequent pregnancy loss among women with recurrent pregnancy loss: An immunological factor-based multivariable model

PROBLEM

Studies on subsequent pregnancy loss prediction models specific for recurrent pregnancy loss (RPL) patients are very limited. This study aims to develop a risk predictive model based on the immunological parameters for the subsequent pregnancy loss risk in northwest Chinese RPL patients.

METHOD OF STUDY

Totally of 357 RPL patients recruited from Lanzhou University Second Hospital were included in this retrospective study. Univariate analysis was performed on RPL patients with outcomes of live birth or pregnancy loss. Subsequently, the least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were utilized to select variables among baseline and clinical characteristics and to develop a pregnancy loss risk prediction model with all 357 RPL patients. The area under the curve (AUC), calibration curve and decision curve analyses were used to evaluate the performance of the prediction model; moreover, 10-fold cross-validation was used for internal validation.

RESULTS

Ten factors of maternal age, age of menarche, previous pregnancy loss, IL-10, complement 4, IgA, antiprothrombin antibody IgG/IgM, rheumatoid factor IgA, and lupus anticoagulant (LA) 1/LA2 ratio were finally selected as variables for the prediction model of pregnancy loss risk. The AUC value and Hosmer-Lemeshow test p-value of the model were .707 and .599, respectively, indicating a satisfactory discrimination and calibration performance. Moreover, the clinical decision curve suggested this prediction model have a good positive net benefit.

CONCLUSIONS

This is the first prediction model for the risk of subsequent pregnancy loss in northwest Chinese women with RPL, providing a user-friendly tool to clinicians for the early prediction and timely management of RPL patients.

Pregnancy outcomes in a malaria-exposed Malian cohort of women of child-bearing age

In Sub-Saharan Africa, malaria continues to be associated with adverse pregnancy outcomes including stillbirth, early neonatal death, preterm delivery, and low birth weight. Current preventive measures are insufficient and new interventions are urgently needed. However, before such interventions can be tested in pregnant women, background information on pregnancy outcomes in this target population must be collected. We conducted an observational study in Ouélessébougou, Mali, a malaria-endemic area where first antenatal visit commonly occurs during the second trimester of pregnancy, hindering calculation of miscarriage rate in the population. To accurately determine the rate of miscarriage, 799 non-pregnant women of child-bearing age were enrolled and surveyed via monthly follow up visits that included pregnancy tests. Out of 505 women that completed the study, 364 became pregnant and 358 pregnancies were analyzed: 43 (12%) resulted in miscarriage, 28 (65.1%) occurred during the first trimester of pregnancy. We also determined rates of stillbirth, neonatal death, preterm delivery, and small for gestational age. The results showed high rate of miscarriage during the first trimester and established a basis to evaluate new interventions to prevent pregnancy malaria. This survey design enabled identification of first trimester miscarriages that are often missed by studies conducted in antenatal clinics.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [NCT0297 4608].

Low molecular weight heparin or LMWH plus aspirin in the treatment of unexplained recurrent miscarriage with negative antiphospholipid antibodies: A meta-analysis of randomized controlled trial

OBJECTIVE

Unexplained recurrent miscarriage (uRM) has caused serious distress to women of childbearing age, and effective treatment is particularly important. The aim of this meta-analysis is to compare the efficacy of low molecular weight heparin (LMWH) and LMWH combined with aspirin for uRM.

METHODS

Databases including PubMed, Web of Science, Embase, Scopus and the Cochrane Library databases were electronically searched to identify randomized controlled trials that reported the LMWH or LMWH combined with aspirin for women with uRM and negative antiphospholipid antibodies (aPL). The retrieval time is limited from inception to June 2021. Two reviewers independently screened literature, extracted data, and assessed risk bias of included studies. Meta-analysis was performed by using STATA 12.0 software.

RESULTS

A total of 7 studies involving 1849 patients were included. The meta-analysis results showed that compared with the control group, both LMWH and LMWH + aspirin interventions showed no substantial influence on miscarriage rate (LMWH: RR = 0.69, 95%CI: 0.34-1.39, P = 0.293, LMWH + aspirin: RR = 0.62, 95%CI: 0.30-1.27, P = 0.19) and the occurrence of pre-eclampsia (LMWH: RR = 1.1, 95%CI: 0.53-2.31, P = 0.792; LMWH + aspirin: RR = 1.49, 95%CI: 0.25-8.79, P = 0.662). LMWH therapy had no influence on the live births (RR = 0.99, 95%CI: 0.92-1.06, P = 0.72). Subgroup analysis showed that enoxaparin is not effective in women with uRM and negative aPL (miscarriage rate: RR = 0.82, 95%CI: 0.31-2.19, P = 0.695; pre-eclampsia: RR = 1.03, 95%CI: 0.46-2.33, P = 0.936).

CONCLUSIONS

LMWH and LMWH combined with aspirin therapy cannot improve the pregnancy outcome of women with uRM and negative aPL. However, the above conclusions are still required to be verified through more RCTs due to the limited quantity of included studies.

Chance of live birth: a nationwide, registry-based cohort study

STUDY QUESTION

Does the sequence of prior pregnancy events (pregnancy losses, live births, ectopic pregnancies, molar pregnancy and still birth), obstetric complications and maternal age affect chance of live birth in the next pregnancy and are prior events predictive for the outcome?

SUMMARY ANSWER

The sequence of pregnancy outcomes is significantly associated with chance of live birth; however, pregnancy history and age are insufficient to predict the outcome of an individual woman's next pregnancy.

WHAT IS KNOWN ALREADY

Adverse pregnancy outcomes decrease the chance of live birth in the next pregnancy, whereas the impact of prior live births is less clear.

STUDY DESIGN, SIZE, DURATION

Nationwide, registry-based cohort study of 1 285 230 women with a total of 2 722 441 pregnancies from 1977 to 2017.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All women living in Denmark in the study period with at least one pregnancy in either the Danish Medical Birth Registry or the Danish National Patient Registry. Data were analysed using logistic regression with a robust covariance model to account for women with more than one pregnancy. Model discrimination and calibration were ascertained using 20% of the women in the cohort randomly selected as an internal validation set.

MAIN RESULTS AND THE ROLE OF CHANCE

Obstetric complications, still birth, ectopic pregnancies and pregnancy losses had a negative effect on the chance of live birth in the next pregnancy. Consecutive, identical pregnancy outcomes (pregnancy losses, live births or ectopic pregnancies) immediately preceding the next pregnancy had a larger impact than the total number of any outcome. Model discrimination was modest (C-index = 0.60, positive predictive value = 0.45), but the models were well calibrated.

LIMITATIONS, REASONS FOR CAUTION

While prior pregnancy outcomes and their sequence significantly influenced the chance of live birth, the discriminative abilities of the predictive models demonstrate clearly that pregnancy history and maternal age are insufficient to reliably predict the outcome of a given pregnancy.

WIDER IMPLICATIONS OF THE FINDINGS

Prior pregnancy history has a significant impact on the chance of live birth in the next pregnancy. However, the results emphasize that only taking age and number of losses into account does not predict if a pregnancy will end as a live birth or not. A better understanding of biological determinants for pregnancy outcomes is urgently needed.

STUDY FUNDING/COMPETING INTEREST(S)

The work was supported by the Novo Nordisk Foundation, Ole Kirk Foundation and Rigshospitalet's Research Foundation. The authors have no financial relationships that could appear to have influenced the work.

TRIAL REGISTRATION NUMBER

N/A.

Perinatal Outcomes in Women with a History of Recurrent Pregnancy Loss

OBJECTIVE

This study aimed to evaluate perinatal outcomes in women with a history of recurrent pregnancy loss.

STUDY DESIGN

Retrospective cohort study of singleton and nonanomalous gestations at ≥ 20 weeks who delivered at our academic institution. The exposed group was defined as women with a history of ≥ 2 consecutive spontaneous abortions (SABs) at < 12 weeks. These women were compared with women with a history of ≤ 1 SAB at < 12 weeks. The primary outcome was preterm birth (PTB) at < 37 weeks. Secondary outcomes included gestational age at delivery, gestational diabetes, small for gestational age birth weight, hypertensive diseases of pregnancy, fetal demise, cesarean delivery, and a composite of neonatal complications (5-minute Apgar score < 5, perinatal death, and NICU admission). Multivariable logistic regression was performed to adjust for confounders.

RESULTS

Of 17,670 women included, 235 (1.3%) had a history of ≥ 2 consecutive SABs. Compared with women with a history of ≤ 1 SAB, women with ≥ 2 consecutive SABs were not more likely to have a PTB (19.6 vs. 14.0%, p = 0.01, adjusted odds ratios (AOR): 0.91, 95% confidence interval [CI]: 0.62-1.33). However, they were more likely to deliver at an earlier mean gestational age (37.8 ± 3.4 vs. 38.6 ± 2.9 weeks, p < 0.01) and to have gestational diabetes (12.3 vs. 6.6%, p < 0.01, AOR: 1.69, 95% CI: 1.10-2.59). Other outcomes were similar between the two groups.

CONCLUSION

A history of ≥ 2 consecutive SABs was not associated with an increased incidence of PTB but may be associated with gestational diabetes in a subsequent pregnancy.

KEY POINTS

· This was a retrospective cohort study.. · Women with a history of recurrent pregnancy loss (RPL) were studied.. · RPL was associated with an increase in preterm birth..

Recurrent pregnancy loss: diagnostic workup after two or three pregnancy losses? A systematic review of the literature and meta-analysis

BACKGROUND

Recurrent pregnancy loss (RPL) occurs in 1–3% of all couples trying to conceive. No consensus exists regarding when to perform testing for risk factors in couples with RPL. Some guidelines recommend testing if a patient has had two pregnancy losses whereas others advise to test after three losses.

OBJECTIVE AND RATIONALE

The aim of this systematic review was to evaluate the current evidence on the prevalence of abnormal test results for RPL amongst patients with two versus three or more pregnancy losses. We also aimed to contribute to the debate regarding whether the investigations for RPL should take place after two or three or more pregnancy losses.

SEARCH METHODS

Relevant studies were identified by a systematic search in OVID Medline and EMBASE from inception to March 2019. A search for RPL was combined with a broad search for terms indicative of number of pregnancy losses, screening/testing for pregnancy loss or the prevalence of known risk factors. Meta-analyses were performed in case of adequate clinical and statistical homogeneity. The quality of the studies was assessed using the Newcastle-Ottawa scale.

OUTCOMES

From a total of 1985 identified publications, 21 were included in this systematic review and 19 were suitable for meta-analyses. For uterine abnormalities (seven studies, odds ratio (OR) 1.00, 95% CI 0.79–1.27, I² = 0%) and for antiphospholipid syndrome (three studies, OR 1.04, 95% CI 0.86–1.25, I² = 0%) we found low quality evidence for a lack of a difference in prevalence of abnormal test results between couples with two versus three or more pregnancy losses. We found insufficient evidence of a difference in prevalence of abnormal test results between couples with two versus three or more pregnancy losses for chromosomal abnormalities (10 studies, OR 0.78, 95% CI 0.55–1.10), inherited thrombophilia (five studies) and thyroid disorders (two studies, OR 0.52, 95% CI: 0.06–4.56).

WIDER IMPLICATIONS

A difference in prevalence in uterine abnormalities and antiphospholipid syndrome is unlikely in women with two versus three pregnancy losses. We cannot exclude a difference in prevalence of chromosomal abnormalities, inherited thrombophilia and thyroid disorders following testing after two versus three pregnancy losses. The results of this systematic review may support investigations after two pregnancy losses in couples with RPL, but it should be stressed that additional studies of the prognostic value of test results used in the RPL population are urgently needed. An evidenced-based treatment is not currently available in the majority of cases when abnormal test results are present.

Pregnancy outcomes, risk factors, and cell count trends in pregnant women with essential thrombocythemia

Pregnancy in essential thrombocythemia (ET) is associated with increased risk of obstetric complications. We retrospectively evaluated risk factors in 121 pregnancies in 52 ET women seen at 3 affiliate hospitals. Univariable and multivariable analyses were performed at the α = 0.10 level. Cell counts were characterized throughout pregnancy and correlated with outcomes using logistic modeling. The overall live birth rate was 69 %. 48.7 % of all women experienced a pregnancy complication, the most common being spontaneous abortion, which occurred in 26 % of all pregnancies. Maternal thrombosis and hemorrhage rates were 2.5 % and 5.8 %. On multivariable analysis, aspirin use (OR 0.29, p = 0.014, 90 % CI 0.118-0.658) and history of prior pregnancy loss (OR 3.86, p = 0.011, CI 1.49-9.15) were associated with decreased and increased pregnancy complications, respectively. A Markov model was used to analyze the probability of a future pregnancy complication based on initial pregnancy outcome. An ET woman who suffers a pregnancy complication has a 0.594 probability of a subsequent pregnancy complication, compared to a 0.367 probability if she didn't suffer a complication. However, despite this elevated risk, overall prognosis is good, with a >50 % probability of a successful pregnancy by the third attempt. Platelet counts decreased by 43 % in ET during pregnancy, with nadir at delivery and prompt recovery in the postpartum period. Women with larger declines in gestational platelet counts were less likely to suffer complications (p = 0.083). Our study provides important guidance to physicians treating ET women during pregnancy, including counseling information regarding risk assessment and expected trajectory of platelet levels.

Gestational age at delivery of twins and perinatal outcomes: a cohort study in Aberdeen, Scotland

Background: Twin pregnancy is associated with a threefold increase in perinatal death compared to singletons.  The objective of this study was to determine the risk of perinatal death in twins by week of gestation and to quantify the effect of known risk factors. Methods: A cohort analysis was performed using data from the Aberdeen Maternity and Neonatal Databank (AMND).  The exposure was gestational age at delivery and the primary outcome was perinatal death.  Adjusted hazard ratios (aHRs) for perinatal death according to gestational age at delivery were determined by multivariate Cox proportional hazards regression modelling with robust standard errors to account for clustering in the twin infants.  Confounders and risk factors quantified and adjusted for in the model included maternal age, smoking, parity, marital status and year of birth.  Kaplan-Meier time to event analysis was used to determine the differences in survival according to chorionicity and assisted reproduction technologies (ART) conception status. Results: The population comprised of 7,420 twin babies born between 1950 and 2013 in the Grampian area of Northern Scotland.  There were 272 stillbirths in the cohort (3.67%) and 273 neonatal deaths (3.68%). Compared to delivery at 37-38 weeks, delivery before 37 weeks was associated with a 2-fold increase in perinatal death. Monochorionic twins had a 2-fold increase in perinatal death compared to dichorionic twins (aHR 2.15, 95% CI 1.60-2.90). Twins conceived by ART did not have a greater risk of perinatal death compared to those naturally conceived (aHR 1.21, 95% CI 0.87-1.68) Conclusion:  This study suggests that delivery of twins at 37-38 weeks is associated with the lowest risk of perinatal death.

Reliability of recurrent pregnancy loss diagnosis coding in the Swedish National Patient Register: a validation study

Background: The Swedish National Patient Registry (NPR) is a nationwide registry that is used extensively for epidemiological research. Using the NPR, we recently found a recurrent pregnancy loss (RPL) incidence of 650/100,000 (0.65%) pregnant women in Sweden. It is of great importance that the quality of the coding is good and reliable in order to use NPR data for research. To specifically study RPL in Sweden, a general validation of this diagnosis in the NPR is needed. Objective: To validate the diagnosis of RPL, defined as ≥3 consecutive miscarriages before 22 gestational weeks, recorded in the NPR and assess how registered miscarriages were verified clinically (ultrasound or urine/serum hCG) by reviewing the medical records. Materials and methods: In a cohort of 6,852 women diagnosed with RPL in Sweden, during 2003-2012, a total of 238 complete medical records from 38 hospitals were reviewed. A power calculation estimated that 228 medical records had to be reviewed for a positive predictive value (PPV) of 85% (95% CI) with a power of 90%. The ICD-10 diagnoses used for RPL were N96.9 and O26.2. Results: The diagnosis of RPL was confirmed in 202 out of 238 medical records resulting in a PPV of 85% (95% CI 78-89%) out of which 59% were verified with ultrasound whereas 35% were verified only by urine/serum hCG. Conclusion: The Swedish NPR is a valuable tool for epidemiological research. We found a high PPV of RPL in the NPR, supporting the use of these data for future research.

Gestational age at delivery of twins and perinatal outcomes: a cohort study in Aberdeen, Scotland

Background: Twin pregnancy is associated with a threefold increase in perinatal death compared to singletons.  The objective of this study was to determine the risk of perinatal death in twins by week of gestation and to quantify the effect of known risk factors. Methods: A cohort analysis was performed using data from the Aberdeen Maternity and Neonatal Databank (AMND).  The exposure was gestational age at delivery and the primary outcome was perinatal death.  Adjusted hazard ratios (aHRs) for perinatal death according to gestational age at delivery were determined by multivariate Cox proportional hazards regression modelling with robust standard errors to account for clustering in the twin infants.  Confounders and risk factors quantified and adjusted for in the model included maternal age, smoking, parity, marital status and year of birth.  Kaplan-Meier time to event analysis was used to determine the differences in survival according to chorionicity and assisted reproduction technologies (ART) conception status. Results: The population comprised of 7,420 twin babies born between 1950 and 2013 in the Grampian area of Northern Scotland.  There were 272 stillbirths in the cohort (3.67%) and 273 neonatal deaths (3.68%). Compared to delivery at 37-38 weeks, delivery at or beyond 39 weeks was associated with a significant increase in perinatal death (aHR 2.00 [95% CI 1.45-2.78]).  Monochorionic twins had a 2-fold increase in perinatal death compared to dichorionic twins (aHR 2.15, 95% CI 1.60-2.90). Twins conceived by ART did not have a greater risk of perinatal death compared to those naturally conceived (aHR 1.21, 95% CI 0.87-1.68) Conclusion:  This study suggests that delivery of twins at 37-38 weeks is associated with the lowest risk of perinatal death.

The role of FAS, FAS-L, BAX, and BCL-2 gene polymorphisms in determining susceptibility to unexplained recurrent pregnancy loss

PURPOSE

Idiopathic recurrent pregnancy loss (RPL) is a multifactorial reproductive disorder where an impaired control of apoptosis is likely involved. Triggering the cell death mechanism occurs in a spatiotemporal manner and is strongly related to a healthy pregnancy. Single nucleotide polymorphisms (SNPs) at the regulatory regions of genes are known to influence the expression patterns of apoptosis-related molecules.

METHODS

A total of 296 unrelated female Brazilian patients were evaluated for clinical-demographic variables and genetic factors: 140 women who had experienced an unexplained RPL (with at least two consecutive abortions) and 156 healthy multiparous women. In all patients, six SNPs were evaluated in genes of apoptosis-related pathways: FAS (rs2234767, rs1800682), FAS-L (rs763110, rs5030772), BAX (rs4645878), and BCL-2 (rs2279115) by PCR followed by a restriction fragment length polymorphism (RFLP)-based analysis.

RESULTS

The BAX-248GA genotype is independently associated with idiopathic RPL [adjusted OR = 0.30, 95% CI 0.13-0.70, P = 0.005] susceptibility. In the same multivariate model, the variables ethnicity, smoking, and alcohol consumption were statistically associated with RPL susceptibility (P < 0.05). No association with RPL susceptibility was reported for the remaining SNPs.

CONCLUSION

Our study is the first to evaluate the role of the main SNPs from both the extrinsic and intrinsic apoptosis pathways in RPL susceptibility. The association of BAX-248G/A with RPL susceptibility suggests that maternal predisposition for RPL has an essential contribution from genes involved in the delicate balance of endometrium cell turnover (cell death/proliferation). Therefore, apoptotic genes may represent promising targets for future studies on healthy pregnancies and the spectrum of pregnancy disorders.

Role of maternal age and pregnancy history in risk of miscarriage: prospective register based study

OBJECTIVES

To estimate the burden of miscarriage in the Norwegian population and to evaluate the associations with maternal age and pregnancy history.

DESIGN

Prospective register based study.

SETTING

Medical Birth Register of Norway, the Norwegian Patient Register, and the induced abortion register.

PARTICIPANTS

All Norwegian women that were pregnant between 2009-13.

MAIN OUTCOME MEASURE

Risk of miscarriage according to the woman's age and pregnancy history estimated by logistic regression.

RESULTS

There were 421 201 pregnancies during the study period. The risk of miscarriage was lowest in women aged 25-29 (10%), and rose rapidly after age 30, reaching 53% in women aged 45 and over. There was a strong recurrence risk of miscarriage, with age adjusted odds ratios of 1.54 (95% confidence interval 1.48 to 1.60) after one miscarriage, 2.21 (2.03 to 2.41) after two, and 3.97 (3.29 to 4.78) after three consecutive miscarriages. The risk of miscarriage was modestly increased if the previous birth ended in a preterm delivery (adjusted odds ratio 1.22, 95% confidence interval 1.12 to 1.29), stillbirth (1.30, 1.11 to 1.53), caesarean section (1.16, 1.12 to 1.21), or if the woman had gestational diabetes in the previous pregnancy (1.19, 1.05 to 1.36). The risk of miscarriage was slightly higher in women who themselves had been small for gestational age (1.08, 1.04 to 1.13).

CONCLUSIONS

The risk of miscarriage varies greatly with maternal age, shows a strong pattern of recurrence, and is also increased after some adverse pregnancy outcomes. Miscarriage and other pregnancy complications might share underlying causes, which could be biological conditions or unmeasured common risk factors.

Application of chromosomal microarray analysis in products of miscarriage

Background

Chromosomal abnormality is one of the major cause of spontaneous abortion. Most available guidelines suggest genetic testing after three miscarriages, which has been proved to be difficult to adhere to and somewhat of low cost-effectiveness. As chromosomal microarray analysis has been recommended to be applied on miscarriage products, we managed a retrospective study on our experience investigate the potential impact of this technique on previous guidelines and our present management on miscarried couples and products.

Results

Of the 405 products of conceptions, the overall detection rate of pathogenetic results was 55.3% (224/405), including 7.1% (16/224) copy number changes which could be missed by conventional karyotyping analysis. Of the 222 natural conception samples, abnormal genetic results were found in 126 cases (56.8%). The detection rate in the assistant reproductive treatment group was 53.6% (98/183). No significant difference was found between these two groups (p = 0.645, OR = 1.110 with 95% CI: 0.713–1.726). The detection rate was 53.2% (75/141) in 141 product-of-conceptions (POCs) of mothers with adverse pregnancy histories. Of the 264 POC samples of mothers without abnormal pregnancy histories, 56.4% (149/264) were genetically abnormal. The detection rate and maternal age between these two groups were all compatible.

Conclusions

Chromosomal microarray testing should be referred to couples at their first miscarriage regardless of the way how they get pregnant.

Treatment efficacy for idiopathic recurrent pregnancy loss - a systematic review and meta-analyses

INTRODUCTION

Medical treatment of women with idiopathic recurrent pregnancy loss is controversial. The objective was to assess the effects of different treatments on live birth rates and complications in women with unexplained recurrent pregnancy loss.

MATERIAL AND METHODS

We searched MEDLINE, Embase and the Cochrane Library, and identified 1415 publications. This systematic review included 21 randomized controlled trials regarding acetylsalicylic acid, low-molecular-weight heparin, progesterone, intravenous immunoglobulin or leukocyte immune therapy in women with three or more consecutive miscarriages of unknown cause. The study quality was assessed and data was extracted independently by at least two authors.

RESULTS

No significant difference in live birth rate was found when acetylsalicylic acid was compared with low-molecular-weight heparin or with placebo. Meta-analyses of low-molecular-weight heparin vs. control found no significant differences in live birth rate [risk ratio (RR) 1.47, 95% CI 0.83-2.61]. Treatment with progesterone starting in the luteal phase seemed effective in increasing live birth rate (RR 1.18, 95% CI 1.09-1.27) but not when started after conception. Intravenous immunoglobulin showed no effect on live birth rate compared with placebo (RR 1.07, 95% CI 0.91-1.26). Paternal immunization compared with autologous immunization showed a significant difference in outcome (RR 1.8, 95% CI 1.34-2.41), although the studies were small and at high risk of bias.

CONCLUSION

The literature does not allow advice on any specific treatment for idiopathic recurrent pregnancy loss, with the exception of progesterone starting from ovulation. We suggest that any treatment for recurrent pregnancy loss should be used within the context of a randomized controlled trial.

Clinical Aspects of Miscarriage

It is estimated that 750,000 to 1,000,000 miscarriages occur every year in the United States. Women experiencing a miscarriage enter the healthcare system in a variety of ways. A family may be seen for a miscarriage in the prenatal clinic, the emergency department, same-day surgical department, or perhaps the labor and birth unit. Nurses must be prepared to guide and support these families. Understanding the clinical aspects of miscarriage as well as the emotional care of families experiencing early pregnancy loss is important to nurses in all areas of the medical center. Clinical aspects of miscarriage are reviewed along with the needed emotional care for families experiencing the most common cause of early pregnancy loss.

Beyond maternal death: improving the quality of maternal care through national studies of ‘near-miss’ maternal morbidity

Background

Studies of maternal mortality have been shown to result in important improvements to women’s health. It is now recognised that in countries such as the UK, where maternal deaths are rare, the study of near-miss severe maternal morbidity provides additional information to aid disease prevention, treatment and service provision.

Objectives

To (1) estimate the incidence of specific near-miss morbidities; (2) assess the contribution of existing risk factors to incidence; (3) describe different interventions and their impact on outcomes and costs; (4) identify any groups in which outcomes differ; (5) investigate factors associated with maternal death; (6) compare an external confidential enquiry or a local review approach for investigating quality of care for affected women; and (7) assess the longer-term impacts.

Methods

Mixed quantitative and qualitative methods including primary national observational studies, database analyses, surveys and case studies overseen by a user advisory group.

Setting

Maternity units in all four countries of the UK.

Participants

Women with near-miss maternal morbidities, their partners and comparison women without severe morbidity.

Main outcome measures

The incidence, risk factors, management and outcomes of uterine rupture, placenta accreta, haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome, severe sepsis, amniotic fluid embolism and pregnancy at advanced maternal age (≥ 48 years at completion of pregnancy); factors associated with progression from severe morbidity to death; associations between severe maternal morbidity and ethnicity and socioeconomic status; lessons for care identified by local and external review; economic evaluation of interventions for management of postpartum haemorrhage (PPH); women’s experiences of near-miss maternal morbidity; long-term outcomes; and models of maternity care commissioned through experience-led and standard approaches.

Results

Women and their partners reported long-term impacts of near-miss maternal morbidities on their physical and mental health. Older maternal age and caesarean delivery are associated with severe maternal morbidity in both current and future pregnancies. Antibiotic prescription for pregnant or postpartum women with suspected infection does not necessarily prevent progression to severe sepsis, which may be rapidly progressive. Delay in delivery, of up to 48 hours, may be safely undertaken in women with HELLP syndrome in whom there is no fetal compromise. Uterine compression sutures are a cost-effective second-line therapy for PPH. Medical comorbidities are associated with a fivefold increase in the odds of maternal death from direct pregnancy complications. External reviews identified more specific clinical messages for care than local reviews. Experience-led commissioning may be used as a way to commission maternity services.

Limitations

This programme used observational studies, some with limited sample size, and the possibility of uncontrolled confounding cannot be excluded.

Conclusions

Implementation of the findings of this research could prevent both future severe pregnancy complications as well as improving the outcome of pregnancy for women. One of the clearest findings relates to the population of women with other medical and mental health problems in pregnancy and their risk of severe morbidity. Further research into models of pre-pregnancy, pregnancy and postnatal care is clearly needed.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Pregnancy loss history at first parity and selected adverse pregnancy outcomes

PURPOSE

To evaluate the association between pregnancy loss history and adverse pregnancy outcomes.

METHODS

Pregnancy history was captured during a computer-assisted personal interview for 21,277 women surveyed in the National Survey of Family Growth (1995-2013). History of pregnancy loss (<20 weeks) at first parity was categorized in three ways: number of losses, maximum gestational age of loss(es), and recency of last pregnancy loss. We estimated risk ratios for a composite measure of selected adverse pregnancy outcomes (preterm, stillbirth, or low birthweight) at first parity and in any future pregnancy, separately, using predicted margins from adjusted logistic regression models.

RESULTS

At first parity, compared with having no loss, having 3+ previous pregnancy losses (adjusted risk ratio (aRR) = 1.66 [95% CI = 1.13, 2.43]), a maximum gestational age of loss(es) at ≥10 weeks (aRR = 1.28 [1.04, 1.56]) or having experienced a loss 24+ months ago (aRR = 1.36 [1.10, 1.68]) were associated with increased risks of adverse pregnancy outcomes. For future pregnancies, only having a history of 3+ previous pregnancy losses at first parity was associated with increased risks (aRR = 1.97 [1.08, 3.60]).

CONCLUSION

Number, gestational age, and recency of pregnancy loss at first parity were associated with adverse pregnancy outcomes in U.S. women.

Aspirin and/or heparin for women with unexplained recurrent miscarriage with or without inherited thrombophilia

BACKGROUND

Since hypercoagulability might result in recurrent miscarriage, anticoagulant agents could potentially increase the chance of live birth in subsequent pregnancies in women with unexplained recurrent miscarriage, with or without inherited thrombophilia.

OBJECTIVES

To evaluate the efficacy and safety of anticoagulant agents, such as aspirin and heparin, in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 October 2013) and scanned bibliographies of all located articles for any unidentified articles.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that assessed the effect of anticoagulant treatment on live birth in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia were eligible. Interventions included aspirin, unfractionated heparin (UFH), and low molecular weight heparin (LMWH) for the prevention of miscarriage. One treatment could be compared with another or with no-treatment (or placebo).

DATA COLLECTION AND ANALYSIS

Two review authors (PJ and SK) assessed the studies for inclusion in the review and extracted the data. If necessary they contacted study authors for more information. We double checked the data.

MAIN RESULTS

Nine studies, including data of 1228 women, were included in the review evaluating the effect of either LMWH (enoxaparin or nadroparin in varying doses) or aspirin or a combination of both, on the chance of live birth in women with recurrent miscarriage, with or without inherited thrombophilia. Studies were heterogeneous with regard to study design and treatment regimen and three studies were considered to be at high risk of bias. Two of these three studies at high risk of bias showed a benefit of one treatment over the other, but in sensitivity analyses (in which studies at high risk of bias were excluded) anticoagulants did not have a beneficial effect on live birth, regardless of which anticoagulant was evaluated (risk ratio (RR) for live birth in women who received aspirin compared to placebo 0.94, (95% confidence interval (CI) 0.80 to 1.11, n = 256), in women who received LMWH compared to aspirin RR 1.08 (95% CI 0.93 to 1.26, n = 239), and in women who received LMWH and aspirin compared to no-treatment RR 1.01 (95% CI 0.87 to 1.16) n = 322).Obstetric complications such as preterm delivery, pre-eclampsia, intrauterine growth restriction and congenital malformations were not significantly affected by any treatment regimen. In included studies, aspirin did not increase the risk of bleeding, but treatment with LWMH and aspirin increased the risk of bleeding significantly in one study. Local skin reactions (pain, itching, swelling) to injection of LMWH were reported in almost 40% of patients in the same study.

AUTHORS' CONCLUSIONS

There is a limited number of studies on the efficacy and safety of aspirin and heparin in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia. Of the nine reviewed studies quality varied, different treatments were studied and of the studies at low risk of bias only one was placebo-controlled. No beneficial effect of anticoagulants in studies at low risk of bias was found. Therefore, this review does not support the use of anticoagulants in women with unexplained recurrent miscarriage. The effect of anticoagulants in women with unexplained recurrent miscarriage and inherited thrombophilia needs to be assessed in further randomised controlled trials; at present there is no evidence of a beneficial effect.

Aspirin and/or heparin for women with unexplained recurrent miscarriage with or without inherited thrombophilia

BACKGROUND

Since hypercoagulability might result in recurrent miscarriage, anticoagulant agents could potentially increase the chance of live birth in subsequent pregnancies in women with unexplained recurrent miscarriage, with or without inherited thrombophilia.

OBJECTIVES

To evaluate the efficacy and safety of anticoagulant agents, such as aspirin and heparin, in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 October 2013) and scanned bibliographies of all located articles for any unidentified articles.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials that assessed the effect of anticoagulant treatment on live birth in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia were eligible. Interventions included aspirin, unfractionated heparin (UFH), and low molecular weight heparin (LMWH) for the prevention of miscarriage. One treatment could be compared with another or with no-treatment (or placebo).

DATA COLLECTION AND ANALYSIS

Two review authors (PJ and SK) assessed the studies for inclusion in the review and extracted the data. If necessary they contacted study authors for more information. We double checked the data.

MAIN RESULTS

Nine studies, including data of 1228 women, were included in the review evaluating the effect of either LMWH (enoxaparin or nadroparin in varying doses) or aspirin or a combination of both, on the chance of live birth in women with recurrent miscarriage, with or without inherited thrombophilia. Studies were heterogeneous with regard to study design and treatment regimen and three studies were considered to be at high risk of bias. Two of these three studies at high risk of bias showed a benefit of one treatment over the other, but in sensitivity analyses (in which studies at high risk of bias were excluded) anticoagulants did not have a beneficial effect on live birth, regardless of which anticoagulant was evaluated (risk ratio (RR) for live birth in women who received aspirin compared to placebo 0.94, (95% confidence interval (CI) 0.80 to 1.11, n = 256), in women who received LMWH compared to aspirin RR 1.08 (95% CI 0.93 to 1.26, n = 239), and in women who received LMWH and aspirin compared to no-treatment RR 1.01 (95% CI 0.87 to 1.16) n = 322).Obstetric complications such as preterm delivery, pre-eclampsia, intrauterine growth restriction and congenital malformations were not significantly affected by any treatment regimen. In included studies, aspirin did not increase the risk of bleeding, but treatment with LWMH and aspirin increased the risk of bleeding significantly in one study. Local skin reactions (pain, itching, swelling) to injection of LMWH were reported in almost 40% of patients in the same study.

AUTHORS' CONCLUSIONS

There is a limited number of studies on the efficacy and safety of aspirin and heparin in women with a history of at least two unexplained miscarriages with or without inherited thrombophilia. Of the nine reviewed studies quality varied, different treatments were studied and of the studies at low risk of bias only one was placebo-controlled. No beneficial effect of anticoagulants in studies at low risk of bias was found. Therefore, this review does not support the use of anticoagulants in women with unexplained recurrent miscarriage. The effect of anticoagulants in women with unexplained recurrent miscarriage and inherited thrombophilia needs to be assessed in further randomised controlled trials; at present there is no evidence of a beneficial effect.

Systematic review and meta-analysis of miscarriage and maternal exposure to tobacco smoke during pregnancy

We conducted a systematic review and meta-analysis to characterize the relationship between smoking and miscarriage. We searched the PubMed database (1956-August 31, 2011) using keywords and conducted manual reference searches of included articles and reports of the US Surgeon General. The full text of 1,706 articles was reviewed, and 98 articles that examined the association between active or passive smoking and miscarriage were included in the meta-analysis. Data were abstracted by 2 reviewers. Any active smoking was associated with increased risk of miscarriage (summary relative risk ratio = 1.23, 95% confidence interval (CI): 1.16, 1.30; n = 50 studies), and this risk was greater when the smoking exposure was specifically defined as during the pregnancy in which miscarriage risk was measured (summary relative risk ratio = 1.32, 95% CI: 1.21, 1.44; n = 25 studies). The risk of miscarriage increased with the amount smoked (1% increase in relative risk per cigarette smoked per day). Secondhand smoke exposure during pregnancy increased the risk of miscarriage by 11% (95% CI: 0.95, 1.31; n = 17 studies). Biases in study publication, design, and analysis did not significantly affect the results. This finding strengthens the evidence that women should not smoke while pregnant, and all women of reproductive age should be warned that smoking increases the risk of miscarriage.

Maternal sepsis: a Scottish population-based case-control study

OBJECTIVE

To describe the risk of maternal sepsis associated with obesity and other understudied risk factors such as operative vaginal delivery.

DESIGN

Population-based, case-control study.

SETTING

North NHS region of Scotland.

POPULATION

All cases of pregnant, intrapartum and postpartum women with International Classification of Disease-9 codes for sepsis or severe sepsis recorded in the Aberdeen Maternal and Neonatal Databank (AMND) from 1986 to 2009. Four controls per case selected from the AMND were frequency matched on year-of-delivery.

METHODS

Cases and controls were compared; significant variables from univariable regression were adjusted in a multivariable logistic regression model.

MAIN OUTCOME MEASURES

Dependent variables were uncomplicated sepsis or severe ('near-miss') sepsis. Independent variables were demographic, medical and clinical delivery characteristics. Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals (95% CI) are reported.

RESULTS

Controlling for mode of delivery and demographic and clinical factors, obese women had twice the odds of uncomplicated sepsis (OR 2.12; 95% CI 1.14-3.89) compared with women of normal weight. Age <25 years (OR 5.15; 95% CI 2.43-10.90) and operative vaginal delivery (OR 2.20; 95% CI 1.02-4.87) were also significant predictors of sepsis. Known risk factors for maternal sepsis were also significant in this study (OR for uncomplicated and severe sepsis respectively): multiparity (OR 6.29, 12.04), anaemia (OR 3.43, 18.49), labour induction (OR 3.92 severe only), caesarean section (OR 3.23, 13.35), and preterm birth (OR 2.46 uncomplicated only).

CONCLUSIONS

Obesity, operative vaginal delivery and age <25 years are significant risk factors for sepsis and should be considered in clinical obstetric care.