Obstetric and perinatal outcomes of women with a history of recurrent pregnancy loss: a meta-analysis of cohort studies

PURPOSE

To assess the risk of adverse obstetric and perinatal outcomes in subsequent pregnancies among women with a history of recurrent pregnancy loss (RPL).

METHODS

Relevant studies were identified by searching the PubMed, Web of Science, and Embase databases. The pooled effect sizes were reported as odds ratios (OR) with their respective 95% confidence intervals (95% CI), and data analysis was performed using the random effects model.

RESULTS

A total of 26 studies involving 4,730,728 women were included in this meta-analysis. The results reveal a significant increase in the prevalence of placenta accreta cases after RPL compared to women without RPL (pooled OR 4.04; 95% CI 1.16-14.15; 2 studies; I2 = 94%; P = 0.03). However, no elevated risk of aneuploidies (pooled OR 1.69, 95% CI 0.73-3.90; 5 studies; I2 = 48%; P = 0.22) or congenital anomalies (pooled OR 1.12, 95% CI 0.97-1.30; 7 studies; I2 = 13%; P = 0.12) in subsequent pregnancies of women with RPL was observed. Additionally, a moderate increase in the risk of various other obstetric and perinatal outcomes was found. The magnitude of the elevated risk of these adverse outcomes varied depending on the region.

CONCLUSIONS

Women with a history of RPL exhibit a significantly elevated risk of placenta accreta in subsequent pregnancies, along with a moderate increase in the risk of various other adverse obstetric and perinatal outcomes. However, RPL does not signify an increased risk of aneuploidies or congenital anomalies in a consecutive pregnancy.

A history of recurrent pregnancy loss is associated with increased perinatal complications, but not necessarily a longer birth interval: a population study spanning 18 years

STUDY QUESTION

Is there a difference in the time interval between the first and second live births among individuals with and without recurrent pregnancy loss (RPL)?

SUMMARY ANSWER

Primary RPL (two or more pregnancy losses before the first live birth) is associated with a shorter time interval between the first and second live births compared with individuals without RPL, but this association is reversed in patients with secondary RPL (RPL patients with no or one pregnancy loss before the first live birth).

WHAT IS KNOWN ALREADY

There is limited information regarding the ability to have more than one child for patients with RPL. Previous studies have investigated the time to live birth and the live birth rate from the initial presentation to clinical providers. Most of the previous studies have included only patients treated at specialized RPL clinics and thus may be limited by selection bias, including patients with a more severe condition.

STUDY DESIGN, SIZE, DURATION

We conducted a population-based retrospective cohort study of 184 241 participants who delivered in British Columbia, Canada, and had at least two recorded live births between 2000 and 2018. The aim was to study the differences in the time interval between the first and second live births and the prevalence of pregnancy complications in patients with and without RPL. Additionally, 198 319 individuals with their first live birth between 2000 and 2010 were studied to evaluate cumulative second live birth rates.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Among individuals with at least two recorded live births between 2000 and 2018, 12 321 patients with RPL and 171 920 participants without RPL were included. RPL was defined as at least two pregnancy losses before 20 weeks gestation. Patients with primary RPL had at least two pregnancy losses occurring before the first live birth, while patients with secondary RPL had no or one pregnancy loss before the first live birth. We compared the time interval from the first to second live birth in patients with primary RPL, those with secondary RPL, and participants without RPL using generalized additive models to allow for a non-linear relationship between maternal age and time interval between first and second live births. We also compared prevalence of pregnancy complications at the first and second live births between the groups using non-parametric Kruskal-Wallis H test and Fisher's exact test for continuous and categorical variables, respectively. We assessed the cumulative second live birth rates in patients with primary RPL and those without RPL, among participants who had their first live birth between 2000 and 2010. Cox proportional hazards model was used to estimate and compare hazard ratios between the two groups using a stratified modelling approach.

MAIN RESULTS AND THE ROLE OF CHANCE

The adjusted time interval between the first and second live births was the longest in patients with secondary RPL, followed by individuals without RPL, and the shortest time interval was observed in patients with primary RPL: 4.34 years (95% CI: 4.09-4.58), 3.20 years (95% CI: 3.00-3.40), and 3.05 years (95% CI: 2.79-3.32). A higher frequency of pregnancy losses was associated with an increased time interval between the first and second live births. The prevalence of pregnancy complications at the first and second live births, including gestational diabetes, hypertensive disorder of pregnancy, preterm birth, and multiple gestations was significantly higher in patients with primary RPL compared with those without RPL. The cumulative second live birth rate was significantly lower in patients with primary RPL compared with individuals without RPL.

LIMITATIONS, REASONS FOR CAUTION

This study may be limited by its retrospective nature. Although we adjusted for multiple potential confounders, there may be residual confounding due to a lack of information about pregnancy intentions and other factors, including unreported pregnancy losses.

WIDER IMPLICATIONS OF THE FINDINGS

The results of this study provide information that will help clinicians in the counselling of RPL patients who desire a second child.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported in part by a grant from the Canadian Institutes of Health Research (CIHR): Reference Number W11-179912. M.A.B. reports research grants from CIHR and Ferring Pharmaceutical. He is also on the advisory board for AbbVie, Pfizer, and Baxter. The other authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

NCT04360564.

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.

Does repetitive dilatation and curettage or hysteroscopic biopsy in patients treated with progestins for endometrial hyperplasia or carcinoma affect subsequent fetomaternal outcomes? A population-based study using the National Health Insurance Research Database of Taiwan

OBJECTIVE

To investigate the impact of repeated dilatation and curettage or hysteroscopic biopsy on fetomaternal outcomes in patients receiving progestin treatment for endometrial hyperplasia or early-stage carcinoma.

METHOD

This was a population-based study using the Taiwan National Health Insurance Research Database between 2009 and 2017 of women who gave birth and had a history of endometrial hyperplasia and early-stage carcinoma treated with progestins. Logistic regression analysis was used to estimate adjusted odds ratios (aORs) with 95% confidence intervals (CIs) reflecting the association between repeated procedures and fetomaternal outcomes.

RESULTS

A total of 6956 women with 8690 deliveries were identified. Compared with those who had two or fewer procedures, women who received more than two procedures had a significantly higher risk for cervical insufficiency (aOR, 5.09 [95 CI, 2.31-11.24]). Furthermore, women who had more than two procedures were prone to have adverse neonatal outcomes, including Apgar score < 7 at 1 min (aOR, 1.97 [95% CI, 1.13-3.43]) and 5 min (aOR, 3.11 [95% CI, 1.33-7.23]) and preterm delivery <32 weeks (aOR, 2.86 [95% CI, 1.50-5.45]).

CONCLUSION

Undergoing more than two procedures was associated with subsequent maternal cervical insufficiency, preterm delivery <32 weeks, and low neonatal Apgar score. Health care providers should be aware of the potential risks and balance the benefits and harms of repeated procedures.

Individual and combined association between nutritional trace metals and the risk of preterm birth in a recurrent pregnancy loss cohort

Background

Recurrent pregnancy loss (RPL) was associated with an elevated risk of pregnancy complications, particularly preterm birth (PTB). However, the risk factors associated with PTB in RPL remained unclear. Emerging evidence indicated that maternal exposure to metals played a crucial role in the development of PTB. The objective of our study was to investigate the individual and combined associations of nutritional trace metals (NTMs) during pregnancy with PTB in RPL.

Methods

Using data from a recurrent pregnancy loss cohort (n = 459), propensity score matching (1:3) was performed to control for covariates. Multiple logistic regression and multiple linear regression were employed to identify the individual effects, while elastic-net regularization (ENET) and Bayesian kernel machine regression (BKMR) were used to examine the combined effects on PTB in RPL.

Results

The logistic regression model found that maternal exposure to copper (Cu) (quantile 4 [Q4] vs. quantile 1 [Q1], odds ratio [OR]: 0.21, 95% confidence interval [CI]: 0.05, 0.74) and zinc (Zn) (Q4 vs. Q1, OR: 0.19, 95%CI: 0.04, 0.77) was inversely associated with total PTB risk. We further constructed environmental risk scores (ERSs) using principal components and interaction terms derived from the ENET model to predict PTB accurately (p < 0.001). In the BKMR model, we confirmed that Cu was the most significant component (PIP = 0.85). When other metals were fixed at the 25th and 50th percentiles, Cu was inversely associated with PTB. In addition, we demonstrated the non-linear relationships of Zn with PTB and the potential interaction between Cu and other metals, including Zn, Ca, and Fe.

Conclusion

In conclusion, our study highlighted the significance of maternal exposure to NTMs in RPL and its association with PTB risk. Cu and Zn were inversely associated with PTB risk, with Cu identified as a crucial factor. Potential interactions between Cu and other metals (Zn, Ca, and Fe) further contributed to the understanding of PTB etiology in RPL. These findings suggest opportunities for personalized care and preventive interventions to optimize maternal and infant health outcomes.

Impact of spontaneous abortion history and induced abortion history on perinatal outcomes of singleton pregnancies

BACKGROUND

At present, there are several studies on abortion history and perinatal outcomes, but there is no unified conclusion whether the history of abortion and different types of abortion are related to perinatal complications of subsequent pregnancy. We aim to study the impact of different types of abortion history on perinatal outcomes of singleton pregnancies.

METHODS

This was a retrospective study from a maternity and infant hospital in Shanghai, China from 2016 to 2020. Pregnant women who gave birth to live singleton infant were included (n = 75,773). We classified abortion into spontaneous abortion (SAB) and induced abortion (IA). We compared the perinatal outcomes of singleton pregnancies with different abortion histories and used Logistic regression analysis to evaluate the associations between pre-pregnancy abortion history with perinatal outcomes.

RESULTS

We observed that pregnant women with a history of abortion were more likely to have a premature delivery (0.99% VS 0.45%), gestational diabetes mellitus (GDM) (13.40% VS 10.29%), placenta abnormality (8.16% VS 5.06%), placenta previa (5.65% VS 3.75%), placenta accreta (0.18% VS 0.04%), and placenta adhesion (2.79% VS 1.03%) than those who obtained singleton pregnancies without a history of abortion. When confounding factors were adjusted, differences in placenta abnormality still existed (excluding placenta abruption). The odds ratios and 95% confidence interval of placenta previa, placenta accreta, and placenta adhesion in pregnant women with only SAB history, only IA history, and both abortion history were 1.294(1.174-1.427), 1.272(1.159-1.396), and 1.390(1.188-1.625), 2.688(1.344-5.374), 2.549(1.268-5.125), and 5.041(2.232-11.386), 2.170(1.872-2.515), 2.028(1.738-2.366), and 3.580(2.917-4.395), respectively.

CONCLUSIONS

Our research showed that pregnant women who have a history of abortion before pregnancy were more likely to have premature birth, GDM, placenta previa, placenta accreta, and placenta adhesion. After adjusting for confounding factors, we found that the history of SAB, IA, and both SAB and IA history were related to the increased risk of placenta previa, placenta accreta, and placenta adhesion.

Pregnancy outcomes following recurrent miscarriage

BACKGROUND

Recurrent miscarriage affects 1-2% of the population, and the literature has focussed on causes, treatment, and live birth rate.

AIM

This study aimed to assess the reproductive outcomes for patients who attended a specialist recurrent miscarriage clinic for investigation and treatment.

METHODS

Prospective analysis of all patients who attended a recurrent miscarriage clinic from January 2014 to January 2021.

RESULTS

Of the 488 patients who attended a specialist clinic, 318 had a further pregnancy with 299 included in this study. The median age was 37 years, with 55.6% having a previous live birth. The subsequent live birth rate was 75.3%, 22.0% had a further pregnancy loss, 1.7% had an ongoing pregnancy, and 1% attended another institution after the second trimester. The rate of preeclampsia was 2.2%, pregnancy-induced hypertension was 2.2%, fetal growth restriction was 5.3%, preterm birth ≤ 34 weeks was 1.8%, and preterm birth > 34 weeks < 37 weeks was 6.6%.

CONCLUSION

Patients who attend a dedicated recurrent miscarriage clinic for investigation and treatment have a high live birth rate in a subsequent pregnancy. A subsequent pregnancy following recurrent pregnancy loss does not appear to be associated with an increased risk of adverse pregnancy outcomes.

Adverse obstetric and perinatal outcomes of patients with history of recurrent miscarriage: a retrospective cohort study

OBJECTIVE

To examine the associations between a history of recurrent miscarriage (RM) and adverse obstetric and perinatal outcomes in the subsequent pregnancy that progressed beyond 24 weeks.

DESIGN

Retrospective cohort study.

SETTING

A large tertiary maternity hospital.

PATIENT(S)

All women who booked for antenatal care and delivery between January 2014 and August 2021 were recorded. The study was limited to women with a singleton pregnancy, and to avoid intraperson correlation, we selected the first record of delivery from each mother in the study, leaving 108,792 deliveries for analysis. Obstetric and perinatal outcomes were compared among 1994 women (1.83%) with a history of ≥2 miscarriages (RM), 11,477 women (10.55%) with a history of 1 miscarriage, and 95,321 women (87.62%) with no history of miscarriage, respectively.

INTERVENTION(S)

Women with a history of ≥2 miscarriages or RM.

MAIN OUTCOME MEASURE(S)

Obstetric complications included gestational diabetes mellitus, preeclampsia (subclassified as preterm and term preeclampsia), placenta previa, placenta accreta, and fetal distress. Perinatal outcomes included emergency cesarean section, elective cesarean section, induction, postpartum hemorrhage, preterm birth, stillbirth, Apgar score <7 at 5 minutes, neonatal asphyxia, neonatal sex, congenital; malformation, low birth weight, and neonatal death.

RESULT(S)

After adjusting for relevant confounders, there was an increased risk of adverse obstetric and perinatal outcomes in a subsequent pregnancy for women with a history of RM, specifically for placental dysfunction disorders: preterm preeclampsia (risk ratio [RR] = 1.58; 95% confidence interval [CI], 1.03-2.32), preterm birth (RR = 1.34; 95% CI, 1.15-1.54)], and abnormal placentation, that is placenta previa (RR = 1.78; 95% CI, 1.36-2.28), and placenta accreta (RR = 4.19; 95% CI, 2.75-6.13).

CONCLUSION(S)

Significant associations existed between a history of RM and the occurrence of adverse obstetric and perinatal outcomes including placental dysfunction disorders and abnormal placentation. These findings may contribute to the early detection and appropriate intervention for placenta-associated diseases in women with a history of RM, with the goal of avoiding or reducing the associated detrimental effects.

The use of immunotherapies for recurrent miscarriage: An overview of systematic reviews and meta-analysis

Immunotherapies have been a treatment proposed for recurrent miscarriages (RMs). The use of immunotherapies remains not recommended in the management of couples with RM. This overview of systematic reviews and meta-analysis (SRs-MAs) aims to identify and evaluate the quality of SRs-MAs that studied the effectiveness of immunotherapies in the treatment of RM patients. SRs-MAs were searched in PubMed/Medline, Embase, and Web of Science. SRs-MAs were analyzed using AMSTAR-2, PRISMA 2020, Risk of Bias in Systematic (ROBIS), and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tools to evaluate the methodological quality, reporting quality, risk of bias, and evidence quality of included SRs-MAs, respectively. This review included 20 SRs-MAs that evaluated the following immunotherapies: intravenous immunoglobulin (13 publications), lymphocyte immunotherapy (6 publications), corticosteroids (3 publications), and lipid emulsion (1 publication). SRs-MAs were rated as high methodological, moderate, and critically low quality in 14 (70 %), 1 (5 %), and 5 (25 %) SRs-MAs and high reporting, moderate, and low quality in 13 (65 %), 4 (20 %), and 3 (5 %) SRs-MAs, respectively. The overall risk of bias revealed a low risk of bias for three-quarters of the SRs-MAs. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) analysis resulted in 23 outcomes, of which 4, 3, 5, and 11 results were of high, moderate, low, and very low quality, respectively. An improvement has been observed over the past few years in the quality of systematic reviews (SR)-MAs that have investigated the efficacy of intravenous immunoglobulin, lymphocyte immunotherapy, lipid emulsion therapy, and corticosteroids as a therapy for RM.

Perinatal outcomes in nulliparous women with a history of multiple pregnancy losses according to number of previous pregnancy losses

BACKGROUND

While it is widely acknowledged that pregnancy losses can lead to negative outcomes for both mothers and fetuses, there is limited information available on the specific levels of risk associated with each additional pregnancy loss.

OBJECTIVE

This study aimed to investigate the effect of number of previous pregnancy losses among nulliparous women on maternal and neonatal adverse outcomes.

STUDY DESIGN

This was a multicenter retrospective cohort study. The study population included all nulliparous women with singleton pregnancies who delivered in all university-affiliated obstetrical centers in a single geographic area between 2003 and 2021. Maternal and neonatal outcomes of women who delivered at our medical centers and had varying numbers of previous pregnancy losses were compared with women who had no previous pregnancy loss. The primary outcome of this study was preterm delivery rate at <37 weeks of gestation. The secondary outcomes were adverse maternal and neonatal outcomes. Univariate analysis was performed using multiple logistic regression modeling.

RESULTS

During the study period, 97,904 nulliparous women met the inclusion and exclusion criteria. Of those women, 84,245 (86%) had no previous pregnancy losses (reference group), 10,724 (11%) had 1 previous pregnancy loss, 2150 (2.2%) had 2 previous pregnancy losses, 516 (0.5%) had 3 previous pregnancy losses, 160 (0.2%) had 4 previous pregnancy losses, and 99 (0.1%) had ≥5 previous pregnancy losses. Women who had previous pregnancy losses had significantly higher rates of preterm delivery, hypertensive disorders of pregnancy, diabetes mellitus (pregestational and gestational), unplanned cesarean delivery, perinatal death, neonatal intensive care unit admissions, and neonatal hypoglycemia. The risks of preterm delivery and most other adverse obstetrical outcomes correlated with the number of previous pregnancy losses. Multivariate analyses showed that each previous pregnancy loss was associated with an additional, significant, increased risk of preterm delivery of 14% at <37 weeks of gestation, 37% at <34 weeks of gestation, 45% at <32 weeks of gestation, and 77% at <28 weeks of gestation.

CONCLUSION

A history of previous pregnancy losses increased the risk of preterm delivery and other perinatal outcomes in a dose-dependent manner. To minimize perinatal complications, obstetricians should be aware of the risks and complications in this unique population, consider close monitoring of the cervical length, and maintain high vigilance in case of complications with special attention to other potentially modifiable risks.

An examination of care received by women with recurrent miscarriage and infertility against guideline-based key performance indicators

OBJECTIVES

International guidelines for the management of recurrent miscarriage (RM) do not provide detailed guidance for the care of women/couples with concurrent infertility. Research studies concerning the investigation and treatment of RM frequently omit this cohort. The aim of this study was to assess the care of women/couples with infertility attending a RM clinic in a large tertiary unit in the Republic of Ireland.

STUDY DESIGN

We conducted an audit of women with RM and infertility attending our RM clinic from 2008 to 2020 against 110 established guideline-based key performance indicators (KPIs) for RM care, encompassing five categories: structure of care, counselling/supportive care, investigation, treatment and outcomes. Information was gathered from documentation from the RM clinic, hospital laboratory and electronic health records.

RESULTS

We identified 128 women with infertility and RM. Information provision in RM clinics regarding modifiable risk factors (71 %; 91/128) and unexplained RM (53 %; 69/128) could be improved. Most women were investigated in line with KPIs, except for pelvic ultrasound (40 %; 51/128), cytogenetic analysis (27 %; 34/128) and 3D ultrasound (2 %; 2/128). Immunotherapies were seldom prescribed (<1%); however, 98 % (125/128) of women received aspirin, 48 % LMWH (62/128) and 16 % corticosteroids (21/128). Surgical interventions were uncommon (5 %; 6/128)). The subsequent pregnancy rate was 70 % (89/128), with 36 % undergoing artificial reproductive technology (32/89). The livebirth rate was 63 % (56/89); 37 % had a further pregnancy loss (33/89), of which two were second-trimester miscarriages.

CONCLUSIONS

Women with RM and infertility received care largely in line with RM guideline-based KPIs. However, we identified areas for improvement, including the quality of information provision, and access to certain investigations. While guideline-based KPIs allow for internationally applicable and reproducible audit that can direct service improvements, the experiences and needs of service-users are not captured, meriting further qualitative research.

Association between Abortion History and Perinatal and Neonatal Outcomes of Singleton Pregnancies after Assisted Reproductive Technology

IMPORTANCE

At present, few people have studied the associations between abortion history before pregnancy on the outcomes of women and their infants after assisted reproductive technology (ART).

OBJECTIVE

To explore the association between the history of abortion and the outcomes of singleton pregnancies after ART.

DESIGN

This was a retrospective study in a hospital from 2015 to 2020 in Shanghai, China. Pregnant women with live singleton births through ART were included (n = 3043). Abortion was classified into spontaneous abortion (SAB) and induced abortion. We compared the maternal and fetal outcomes of singleton pregnancies obtained through ART with different abortion histories. Logistic regression analysis was used to evaluate the associations between the history of pre-pregnancy abortion with perinatal complications and neonatal outcomes.

RESULTS

We observed that compared with those who had no abortion history and obtained singleton pregnancies through ART, women who had an abortion history before pregnancy (including SAB or induced abortion history) and only SAB history were more likely to have gestational diabetes mellitus (GDM), thyroid-related diseases, and placenta-related diseases. After adjusting the potential confounding factors, these differences still existed. The adjusted odds ratios (ORs) and 95% confidence interval (CI) of GDM, thyroid-related diseases, and placenta-related diseases in women with a history of abortion and only a history of SAB were 1.239 (1.030-1.492) and 1.240 (1.010-1.522), 1.589 (1.261-2.002) and 1.724 (1.344-2.213), 1.465 (1.183-1.815) and 1.433 (1.132-1.814), respectively. However, we did not observe the association between the history of induced abortion and GDM and thyroid-related diseases.

CONCLUSIONS AND RELEVANCE

Our research showed that pregnant women with singleton pregnancies through ART who had a history of abortion or only a history of SAB were more likely to have GDM, thyroid-related diseases, and placenta-related diseases. Pregnant women who had both SAB and induced abortion before pregnancy had a higher risk of thyroid-related diseases and placenta-related diseases, while women who had only a history of induced abortion had a higher risk of placenta-related diseases. Further research is needed to explore the biological mechanism of different types of abortion related to subsequent pregnancy.

Does a history of recurrent pregnancy loss affect subsequent obstetric outcomes and placental findings in in vitro fertilization?

PURPOSE

To assess perinatal outcomes and placental findings in in vitro fertilization (IVF) patients with previous recurrent pregnancy loss (RPL).

METHODS

This was a retrospective cohort of live singleton births following IVF at a single university-affiliated center between 2009 and 2017. Outcomes were compared between patients with previous RPL, defined as two miscarriages (RPL group), and patients without RPL (control group). Placental examination was performed for all deliveries irrelevant of complications, and findings categorized according to the Amsterdam Placental Workshop Consensus.

RESULTS

One hundred seventy-two deliveries of women with previous RPL (RPL group) were compared to 885 controls. Maternal age, 36.2 ± 4.2 vs. 35.4 ± 4.2 years, p = 0.02, and rate of uterine fibroids, 12.7% vs. 7.3%, p = 0.01, were higher in the RPL group. The rate of nulliparity was lower in the RPL group, 63.3% vs. 74.1%, p = 0.003. Unexplained infertility and diminished ovarian reserve were more common in the RPL group and male factor infertility in controls. There was a lower rate of fresh embryo transfer in the RPL group, 50.5% vs. 64.7%, p < 0.001, and reduced endometrial thickness. Similar obstetric outcomes were noted in the groups after adjustment for confounders. Placental examinations were notable for lower placental thickness, β - 0.17 cm, 95%CI - 0.30-(- 0.0), a lower rate of velamentous cord insertion, aOR 0.44, 95%CI 0.20-0.95, and a higher rate of villous infarction, aOR 2.82, 95%CI 1.28-6.20 in the RPL group.

CONCLUSION

In IVF patients with a history of RPL, subsequent deliveries were associated with a limited number of placental lesions, yet with similar obstetric outcomes.

A predicting model of child-bearing-aged women' spontaneous abortion by co-infections of TORCH and reproductive tract

To develop a predicting model of child-bearing-aged women' spontaneous abortion (SA) by co-infections of TORCH and reproductive tract, in order to provide a reference tool for accurately predicting the risk of SA and guide the early prevention, diagnosis and treatment of SA. A prospective cohort study was designed based on 218 958 child-bearing-aged women following up in Hebei province in China from 2010 to 2017. Multivariable logistic regression analysis was used to select candidate predictive variables. Fisher's discriminant analysis was performed to build a predictive model, and the validity of the model was evaluated. The incidence rate of SA was 2.4%. Multivariable logistic regression analysis showed that age (OR = 3.507), adverse pregnancy history (OR = 1.509), co-infections status of Candida and HBsAg (OR_{Candida positive×HBsAg negative}  = 4.091, OR_{Candida negative×HBsAg positive}  = 3.327, and OR_{Candida positive×HBsAg positive}  = 13.762), and co-infections status of HBsAg, Rubella (IgG) and CMV (IgG) (OR_{HBs-Ag negative×Rubella (IgG) negative×CMV (IgG) positive}  = 1.789, OR_{HBs-Ag positive×Rubella (IgG) positive×CMV (IgG) negative}  = 3.809, and OR_{HBsAg positive×Rubella (IgG) positive×CMV (IgG) positive}  = 11.919) were the independent predictors of SA. The total discriminant rate reached 91%, with 82% of the sensitivity and 91% of the specificity. The predicting model of child-bearing-aged women' SA by co-infections status has a good performance. The co-infection status of TORCH and reproductive tract are suggested to be considered in pre-pregnancy physical examination.

Plasma level of mannose-binding lectin is associated with the risk of recurrent pregnancy loss but not pregnancy outcome after the diagnosis

STUDY QUESTION

Are low or high plasma mannose-binding lectin (p-MBL) levels associated with recurrent pregnancy loss (RPL) and the reproductive and perinatal outcomes before and after RPL?

SUMMARY ANSWER

The prevalence of low p-MBL levels was significantly higher in RPL patients, while high levels were significantly less prevalent. No association was found between p-MBL level and reproductive and perinatal outcomes before and after RPL.

WHAT IS KNOWN ALREADY

Mannose-binding lectin (MBL) is an important component in the innate immune system. Low p-MBL levels have been associated with RPL, while the correlation with high levels has been poorly studied. Adverse perinatal outcomes are generally more frequent among RPL patients, but reports concerning the association between maternal p-MBL levels and perinatal outcomes, including birth weight (BW) and gestational age (GA), are conflicting.

STUDY DESIGN, SIZE, DURATION

This study was a combined cross-sectional and cohort study of 267 RPL patients admitted to the RPL Center of Western Denmark between January 2016 and March 2020. RPL patients were followed until birth of a liveborn child or until end of follow-up, March 2021. A sample of 185 healthy female blood donors of reproductive age was used as a MBL reference group.

PARTICIPANTS/MATERIALS, SETTING, METHODS

All RPL patients had ≥3 consecutive pregnancy losses, a regular menstrual cycle and no known significant chromosomal or uterine malformations. At the first consultation, routine blood samples including p-MBL measurement and detailed obstetrical and perinatal information were collected. p-MBL levels in RPL patients were compared to the MBL reference group. A logistic regression analysis adjusted for relevant confounders assessed the association between low p-MBL levels and an unsuccessful reproductive outcome in RPL patients in first pregnancy after admission. Perinatal outcomes before and after RPL were compared between RPL subgroups according to low (≤500 µg/l), intermediate (501–3000 µg/l) and high (>3000 µg/l) p-MBL levels.

MAIN RESULTS AND THE ROLE OF CHANCE

Significantly more RPL patients had low p-MBL levels (prevalence proportion ratio (PPR): 1.79, 95% CI: 1.34–2.38) and fewer had high p-MBL levels (PPR: 0.56, 95% CI: 0.40–0.79) compared to the reference group, while the prevalence of intermediate p-MBL level was not different between the groups (PPR: 0.86, 95% CI: 0.69–1.08). In the prospective study, low p-MBL level was not a significant risk factor for a pregnancy loss in the first pregnancy after admission after adjustment for age, BMI and smoking. Neither before nor after the RPL diagnosis were maternal p-MBL levels significantly associated with BW or GA.

LIMITATIONS, REASONS FOR CAUTION

Only 161 (60.3%) patients had given birth after RPL during the follow-up period, which limited the possibility to detect clear associations between p-MBL levels and perinatal outcomes after RPL.

WIDER IMPLICATIONS OF THE FINDINGS

In agreement with several previous studies, low p-MBL levels are strongly associated with RPL, while this study for the first time documents that high levels may play a protective role, which suggests a causal relationship. We suggest that larger prospective studies evaluate the association between p-MBL levels and RPL prognosis.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was received. We acknowledge the Department of Obstetrics and Gynaecology at Aalborg University Hospital for financial support. U.S.K. has reported personal fees from Merck, consulting fees from IBSA Nordic, and a grant from Gedeon Richter, Merck and IBSA Nordic outside of the submitted work.

TRIAL REGISTRATION NUMBER

ID from clinicaltrials.gov is NCT04017754.

Defining recurrent implantation failure: a profusion of confusion or simply an illusion?

Recurrent implantation failure (RIF) is a poorly defined clinical scenario marked by failure to achieve pregnancy after multiple embryo transfers. The causes and definitions of implantation failure are heterogeneous, posing limitations on study design as well as the interpretation and application of findings. Recent studies suggest a novel, personalized approach to defining RIF. Here, we review the implantation physiology and definitions of the implantation rate, failure, and RIF.

Obstetric and neonatal outcomes of pregnancies resulting from preimplantation genetic testing: a systematic review and meta-analysis

BACKGROUND

Preimplantation genetic testing (PGT) includes methods that allow embryos to be tested for severe inherited diseases or chromosomal abnormalities. In addition to IVF/ICSI and repeated freezing and thawing of the embryos, PGT requires a biopsy to obtain embryonic genetic material for analysis. However, the potential effects of PGT on obstetric and neonatal outcomes are currently uncertain.

OBJECTIVE AND RATIONALE

This study aimed to investigate whether pregnancies conceived after PGT were associated with a higher risk of adverse obstetric and neonatal outcomes compared with spontaneously conceived (SC) pregnancies or pregnancies conceived after IVF/ICSI.

SEARCH METHODS

PubMed, EMBASE, MEDLINE, Web of Science and The Cochrane Library entries from January 1990 to January 2021 were searched. The primary outcomes in this study were low birth weight (LBW) and congenital malformations (CMs), and the secondary outcomes included gestational age, preterm delivery (PTD), very preterm delivery (VPTD), birth weight (BW), very low birth weight (VLBW), neonatal intensive care unit (NICU) admission, hypertensive disorders of pregnancy (HDP), gestational diabetes, placenta previa and preterm premature rupture of membranes (PROM). We further pooled the results of PGT singleton pregnancies. Subgroup analyses included preimplantation genetic diagnosis (PGD), preimplantation genetic screening (PGS), cleavage-stage biopsy combined with fresh embryo transfer (CB-ET) and blastocyst biopsy combined with frozen-thawed embryo transfer (BB-FET).

OUTCOMES

This meta-analysis included 15 studies involving 3682 babies born from PGT pregnancies, 127 719 babies born from IVF/ICSI pregnancies and 915 222 babies born from SC pregnancies. The relative risk (RR) of LBW was higher in PGT pregnancies compared with SC pregnancies (RR = 3.95, 95% confidence interval [CI]: 2.32-6.72), but the risk of CMs was not different between the two groups. The pooled results for the risks of LBW and CMs were similar in PGT and IVF/ICSI pregnancies. The risks of PTD (RR = 3.12, 95% CI: 2.67-3.64) and HDP (RR = 3.12, 95% CI: 2.18-4.47) were significantly higher in PGT pregnancies compared with SC pregnancies. Lower gestational age (mean difference [MD] = -0.76 weeks, 95% CI -1.17 to -0.34) and BW (MD = -163.80 g, 95% CI: -299.35 to -28.24) were also noted for PGT pregnancies compared with SC pregnancies. Nevertheless, compared with IVF/ICSI pregnancies, the risks of VPTD and VLBW in PGT pregnancies were significantly decreased by 41% and 30%, respectively, although the risk of HDP was still significantly increased by 50% in PGT pregnancies compared with IVF/ICSI pregnancies. The combined results of obstetric and neonatal outcomes of PGT and IVF/ICSI singleton pregnancies were consistent with the overall results. Further subgroup analyses indicated that both PGD and PGS pregnancies were associated with a higher risk of PTD and a lower gestational age compared with SC pregnancies.

WIDER IMPLICATIONS

This meta-analysis showed that PGT pregnancies may be associated with increased risks of LBW, PTD and HDP compared with SC pregnancies. The overall obstetric and neonatal outcomes of PGT pregnancies are favourable compared with those of IVF/ICSI pregnancies, although PGT pregnancies were associated with a higher risk of HDP. However, because the number of studies that could be included was limited, more randomised controlled trials and prospective cohort studies are needed to confirm these conclusions.

Maternal and fetal safety of intravenous immunoglobulin in women with reproductive failure

PROBLEM

Intravenous immunoglobulin G (IVIG) is an emerging regimen for women with reproductive failures (RF) during- or pre-pregnancy who have aberrant cellular immune reactions. Studies investigating teratogenicity of IVIG have been limited. Herein, we evaluated the fetal teratogenicity of IVIG and IVIG-related obstetric complications.

METHOD OF STUDY

Women who used IVIG during pregnancy due to RF with cellular immune aberrances were enrolled from four medical centers in Korea. The pregnancy outcomes were collected.

RESULTS

A total of 370 RF women who used IVIG during their pregnancy were enrolled. Most of the patients started the IVIG therapy before 12 weeks of gestation and 229 women continued IVIG treatment beyond 12 weeks of gestation. The mean age of the subjects was 34.8 years and the mean total dosage of IVIG was 125.3 g. A total of 307 women had livebirths and six of them were twins. Of 301 singleton livebirths, obstetric complications were developed as follows: preterm births (12.0%), gestational diabetes (7.0%), preeclampsia (4.0%), placental abruption (1.3%), placenta previa (4.3%), and placenta accrete (1.7%). Total six cases (1.99%) had major fetal anomalies in livebirths. The incidence of birth defects is similar to those of the general population in Korea and the previous report in infertile women. No IVIG -related viral contamination was noted.

CONCLUSION

IVIG use during pregnancy did not increase obstetric complications and fetal teratogenicity. This study can be an evidence of maternal and fetal safety of IVIG administration during pregnancy.

Clinical consequences of defective decidualization

Decidualization is characterized by a series of genetic, metabolic, morphological, biochemical, vascular and immune changes occurring in the endometrial stroma in response to the implanting embryo or even before conception and involves the stromal cells of the endometrium. It is a fundamental reproductive event occurring in mammalian species with hemochorial placentation. A growing body of experimental and clinical evidence strongly suggests that defective or disrupted decidualization contributes to the establishment of an inappropriate maternal-fetal interface. This has relevant clinical consequences, ranging from recurrent implantation failure and recurrent pregnancy loss in early pregnancy to several significant complications of advanced gestation. Moreover, recent evidence indicates that selected diseases of the endometrium, such as chronic endometritis and endometriosis, can have a detrimental impact on the decidualization response in the endometrium and may help explain some aspects of the reduced reproductive outcome associated with these conditions. Further research efforts are needed to fully understand the biomolecular mechanisms ans events underlying an abnormal decidualization response. This will permit the development of new diagnostic and therapeutic strategies aimed to improve the likelihood of achieveing a successful pregnancy.

Women with a History of Recurrent Pregnancy Loss Are a High-Risk Population for Adverse Obstetrical Outcome: A Retrospective Cohort Study

Recurrent pregnancy loss (RPL), defined as three or more consecutive miscarriages, is hypothesized to share some of the same pathogenic factors as placenta-associated disorders. It has been hypothesized that a defect implantation causes pregnancy loss, while a partially impaired implantation may lead to late pregnancy complications. The aim of this retrospective register-based cohort study was to study the association between RPL and such disorders including pre-eclampsia, stillbirth, small for gestational age (SGA) birth, preterm birth and placental abruption. Women registered with childbirth(s) in the Swedish Medical Birth Register (MFR) were included in the cohort. Pregnancies of women diagnosed with RPL (exposed) in the National Patient Register (NPR), were compared with pregnancies of women without RPL (unexposed/reference). Obstetrical outcomes, in the first pregnancy subsequent to the diagnosis of RPL (n = 4971), were compared with outcomes in reference-pregnancies (n = 57,410). Associations between RPL and placental dysfunctional disorders were estimated by odds ratios (AORs) adjusting for confounders, with logistic regression. RPL women had an increased risk for pre-eclampsia (AOR 1.45; 95% CI; 1.24-1.69), stillbirth <37 gestational weeks (GWs) (AOR 1.92; 95% CI; 1.22-3.02), SGA birth (AOR 1.97; 95% CI; 1.42-2.74), preterm birth (AOR 1.46; 95% CI; 1.20-1.77), and placental abruption <37 GWs (AOR 2.47; 95% CI; 1.62-3.76) compared with pregnancies by women without RPL. Women with RPL had an increased risk of pregnancy complications associated with placental dysfunction. This risk population is, therefore, in need of improved antenatal surveillance.

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

Recurrent pregnancy loss is a distressing pregnancy disorder experienced by ~2.5% of women trying to conceive. Recurrent pregnancy loss is defined as the failure of two or more clinically recognized pregnancies before 20-24 weeks of gestation and includes embryonic and fetal losses. The diagnosis of an early pregnancy loss is relatively straightforward, although progress in predicting and preventing recurrent pregnancy loss has been hampered by a lack of standardized definitions, the uncertainties surrounding the pathogenesis and the highly variable clinical presentation. The prognosis for couples with recurrent pregnancy loss is generally good, although the likelihood of a successful pregnancy depends on maternal age and the number of previous losses. Recurrent pregnancy loss can be caused by chromosomal errors, anatomical uterine defects, autoimmune disorders and endometrial dysfunction. Available treatments target the putative risk factors of pregnancy loss, although the effectiveness of many medical interventions is controversial. Regardless of the underlying aetiology, couples require accurate information on their chances of having a baby and appropriate support should be offered to reduce the psychological burden associated with multiple miscarriages. Future research must investigate the pathogenesis of recurrent pregnancy loss and evaluate novel diagnostic tests and treatments in adequately powered clinical trials.

Impact of Recurrent Miscarriage on Maternal Outcomes in Subsequent Pregnancy: The Mutaba'ah Study

Purpose

To estimate the prevalence of recurrent miscarriage (RM) and investigate the association between RM and adverse maternal outcomes in subsequent pregnancies.

Participants and Methods

This is an interim analysis of a prospective study of 1737 pregnant women with gravidity of two or more prior to the current pregnancy. These women joined the Mutaba’ah Study between May 2017 and April 2019 and were followed up until they delivered. Hospital medical records were used to extract data on past pregnancy history and the progress and outcomes of the current pregnancy, such as gestational diabetes, preeclampsia, mode of delivery, preterm delivery, and complications at birth.

Results

Amongst pregnant women with at least two previous pregnancies (n=1737), there were 234 (13.5%) women with a history of two or more consecutive miscarriages. Women with RM were slightly older, more parous, and more likely to have had previous infertility treatment (all p-values <0.05). Women with a history of RM had independently significant increased odds of cesarean section (adjusted odds ratio (aOR) 1.81, 95% CI 1.24–2.65) and preterm (<37 weeks, aOR: 2.52, 95% CI 1.56–4.08) or very preterm delivery (<32 weeks, aOR: 7.02 95% CI 2.41–20.46) in subsequent pregnancies than women who did not have a history of RM.

Conclusion

Women with a history of RM were twice as likely to undergo cesarean section and seven times more likely to deliver prior to 32 weeks of gestation than women without a history of RM. The study findings support the need for early pregnancy monitoring or assessment units to ensure better follow-up and customized care for at-risk pregnant women with a history of RM.

Pregnancy-Related Complications in Women with Recurrent Pregnancy Loss: A Prospective Cohort Study

The aim of this prospective cohort study was to determine whether women with recurrent pregnancy loss (RPL) have an increased risk of pregnancy complications compared to normal pregnant women. A total of 1092 singleton pregnancies were followed, 431 in women with RPL and 661 in normal healthy women. The prevalence of the following complications was observed: threatened miscarriage, miscarriage, cervical insufficiency, chromosomal/genetic abnormalities, fetal anomalies, oligohydramnios, polyhydramnios, fetal growth restriction, intrauterine fetal death, gestational diabetes mellitus (GDM), preeclampsia, placenta previa, abruptio placentae, pregnancy-related liver disorders, and preterm premature rupture of the membranes. The odds ratio and 95% CI for each pregnancy complication considered were determined by comparing women with RPL and normal healthy women. Women with RPL had an overall rate of pregnancy complications higher than normal women (OR = 4.37; 95% CI: 3.353–5.714; p < 0.0001). Their risk was increased for nearly all the conditions considered. They also had an increased risk of multiple concomitant pregnancy complications (OR = 4.64; 95% CI: 3.10–6.94, p < 0.0001). Considering only women with RPL, women with ≥3 losses had a higher risk of pregnancy complications than women with two losses (OR = 1.269; 95% CI: 1.112–2.386, p < 0.02). No differences were found in the overall risk of pregnancy complications according to the type, explained or unexplained, of RPL. Women with secondary RPL had an increased risk of GDM than women with primary RPL. Pregnancy in women with RPL should be considered at high risk.

Effect of periconceptional folic acid supplementation on the risk of neural tube defects associated with a previous spontaneous abortion or maternal first-trimester fever

STUDY QUESTION

Does maternal periconceptional no folic acid supplementation have an increased risk of neural tube defects (NTDs) associated with previous spontaneous abortion or first-trimester fever?

SUMMARY ANSWER

Maternal periconceptional no folic acid supplementation can increase the risk of NTDs associated with previous spontaneous abortion or first-trimester fever, independent of known confounding factors.

WHAT IS KNOWN ALREADY

Maternal periconceptional folic acid deficiency can increase the risk of NTDs. However, whether an interaction between periconceptional no folic acid supplementation and history of spontaneous abortion or first-trimester fever may have an increased risk of NTDs remains unknown.

STUDY DESIGN, SIZE, DURATION

A population-based case-control study was performed including 104 nuclear families with offspring with NTDs and 100 control families with normal offspring between 1993 and 2002.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We investigated the potential interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion or first-trimester fever in the risk for NTDs. Information on exposure factors was obtained at the onset of pregnancy, and pregnancy outcomes were collected during the first week after delivery or at the time of termination of the pregnancy. A multivariate logistic regression analysis was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

The interaction between periconceptional no folic acid use and a maternal history of spontaneous abortion markedly increased the risk of NTDs (adjusted odds ratio (aOR) 18.68, 95% CI, 4.43-78.76) after adjusting for potential confounding factors. The interaction coefficient was found to be 2.08, higher than 1, indicating that there is a significant interaction between two factors. Mothers who did not take periconceptional folic acid and had first-trimester fever had an increased risk of NTDs (aOR 21.81, 95% CI, 8.81-80.73). However, the interaction coefficient was found to be 0.62, less than 1, indicating that there is no significant interaction between two factors.

LIMITATIONS, REASONS FOR CAUTION

A potential limitation was that the interval between the previous spontaneous abortion and the beginning of the subsequent pregnancy could not be estimated accurately, but was at least 1 year or more.

WIDER IMPLICATIONS OF THE FINDINGS

We emphasize that a previous spontaneous abortion may represent a first occurrence of NTDs rather than be the cause of NTDs. Our findings indicate that mothers with a history of spontaneous abortion are ideal candidates for periconceptional folic acid supplementation.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by National Natural Science Foundation of China (41871360) and Danone Nutrition Center for Dietary Nutrition Research and Education Foundation (DIC2015-05). There are no competing interests to declare.

Pregnancy complications recur independently of maternal vascular malperfusion lesions

BACKGROUND

Spontaneous abortions, intrauterine growth restriction, and preeclampsia are thought to be caused by defective placentation and are associated with increased risk of adverse outcomes in subsequent pregnancies. However, it is not known whether the recurrence of adverse outcomes is associated with the recurrence of placental pathology. We hypothesized that recurrent maternal vascular malperfusion (MVM) underlies the recurrence of adverse outcomes.

METHODS

Using data from the National Collaborative Perinatal Project, we assessed the recurrence of pregnancy complications and MVM lesions (N = 3865), associations between a history of spontaneous abortions and MVM lesions or adverse outcomes in subsequent pregnancies (N = 8312), and whether the recurrence of pregnancy complications occurred independently of the presence of MVM lesions.

RESULTS

The odds of an MVM lesion were higher for a woman who had had an MVM lesion in a previous pregnancy (aOR = 1.6; 95% CI 1.3-1.9), although this was marginally non-significant after adjusting for covariates such as gestational age, race and BMI. The odds of preeclampsia, a small-for-gestational-age infant, premature delivery and early pregnancy loss were 2.7-5.0 times higher if there had been that same adverse outcome in a previous pregnancy. A history of spontaneous abortions was associated with higher risk of a small-for-gestational-age baby (aOR = 2.4; 95% CI 1.7-3.4) and prematurity (aOR = 5.1; 95% CI 2.3-11.5 for extremely preterm), but not preeclampsia. The recurrence of adverse outcomes was significant when restricting analyses to women without MVM lesions. Similarly, associations between adverse outcomes and previous spontaneous abortions were significant when statistically controlling for the presence of MVM lesions, or excluding pregnancies with MVM lesions.

CONCLUSIONS

Women with adverse outcomes in one pregnancy are at higher risk of complications in subsequent pregnancies. However, there is significant recurrence of adverse outcomes even in the absence of MVM.

Inherited susceptibility to miscarriage: a nested case-control study of 31,565 women from an intergenerational cohort

BACKGROUND

Miscarriage can be a devastating outcome for couples, and most miscarriages are unexplained. Many adverse obstetric outcomes (such as preeclampsia, preterm birth, and growth restriction) are thought to be inherited. It is possible that these conditions could share similar pathophysiologic mechanisms (such as endothelial dysfunction) with miscarriage. Therefore, it was hypothesized that there could be a susceptibility to miscarriage transmitted from mother to daughter.

OBJECTIVE

This study aimed to investigate the association between a maternal history of miscarriage and the risk of miscarriage in daughters.

STUDY DESIGN

A case-control study nested within an intergenerational cohort was conducted. Mother-daughter pairs were identified from the intergenerational cohort within the Aberdeen Maternity and Neonatal Databank, United Kingdom. A mother's history of miscarriage was the exposure. The primary outcome was miscarriage in daughters. There were 31,565 mother-daughter pairs who were eligible for inclusion. A population average model that used generalized estimating equations with robust standard errors was used to estimate the odds of a mother's history of miscarriage in daughters with a miscarriage compared with daughters with only livebirths. This method accounted for clustering of daughters within mothers, and multiadjusted analyses were performed to include confounders at the daughter's pregnancy level.

RESULTS

Daughters who miscarried had 11% greater odds of being born to mothers with a history of miscarriage (adjusted odds ratio, 1.11; 95% confidence interval, 1.01-1.22). Daughters with recurrent miscarriage (≥2) were also more likely to be born to a mother with a history of miscarriage (adjusted odds ratio, 1.25; 95% confidence interval, 1.04-1.49).

CONCLUSION

There may be an inherited predisposition to miscarriage transmitted from mother to daughter. Future research should investigate genetic or familial environmental factors that may predispose women to miscarriage.

Subsequent pregnancy outcomes following second trimester miscarriage-A prospective cohort study

OBJECTIVES

Pregnancy after second-trimester miscarriage represents as clinical challenge. This study sought to determine the rates of recurrence, preterm birth and live births in a cohort of 185 women with previous second-trimester miscarriage. We hypothesized that there would be a higher rate of second-trimester miscarriage and preterm birth in subsequent pregnancy after second trimester miscarriage. The primary objectives of this study were to establish rates of second-trimester miscarriage, preterm birth and live births in this cohort. Secondary objectives were to examine medical and surgical interventions, in addition to other pregnancy outcomes and complications.

STUDY DESIGN

This was a prospective cohort study carried out in a tertiary referral center in southern Ireland with over 8000 deliveries per year. 175 women were followed up. Inclusion criteria were an ultrasound confirmed second-trimester miscarriage between June 2009 and June 2013 and subsequently having a pregnancy between July 2009 and January 2016. Fifty-five women did not become pregnant during the study period and were excluded. Ten women were excluded for missing data.

RESULTS

Between July 2009 and January 2016, 110 women became pregnant following a previous second-trimester miscarriage. In total, 81 babies were born to 77 mothers. The recurrence rate of second-trimester miscarriage was 6.3% (7/110) and the preterm birth rate was also 6.3% (7/110). The cesarean section rate was 45%. Including those who experienced first or second trimester miscarriage, 47% (78/155) of those who were followed up did not go on to have a live infant.

CONCLUSIONS

Women experiencing second-trimester miscarriage are at increased risk in subsequent pregnancies of recurrence. Second-trimester miscarriage needs to be highlighted as a risk factor for adverse pregnancy outcomes. Greater research into its pathophysiology is required to advance preventative measures.

Gestational and perinatal outcomes in recurrent miscarriages couples treated with lymphocyte immunotherapy

Objective

This study aims to elucidate which types of recurrent miscarriage (RM) patients experienced a livebirth after paternal lymphocyte immunotherapy (LIT) and to evaluate the perinatal outcome.

Study design

Retrospective analysis of a multicenter, observational study which enrolled 1096 couples with a history of two or more spontaneous miscarriages without any intercalated delivery. We conducted an intention-to-treat analysis of couples with RM treated with or without LIT regarding to gestational and perinatal outcomes. We compared groups by using the Student’s t-test or Kruskal–Wallis test, Fisher’s exact-test and χ² test when appropriate.

Results

The success of gestation was significantly higher in the LIT group (60.1% vs. 33.1%; p <  0.001). A sub-analysis of four different immune disorder groups revealed a significantly higher success in the LIT group in all immune categories, except in patients who had autoantibodies positive. We observed no significant differences in perinatal outcomes such as gestational age at birth, preterm and extreme preterm birth, and birth weight in successful pregnancy in both groups. The success rate was significantly higher when LIT was administrated before and during pregnancy and only during pregnancy compared to only before pregnancy (p <  0.01).

Conclusions

Careful laboratory test phenotyping of RM patients may identify subgroups most likely to benefit and exclude those with little likelihood of benefit, and LIT during a pregnancy may significantly improve success rates.

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.

Results of a Dutch national and subsequent international expert meeting on interconception care

Introduction: The potential value of preconception care and interconception care is increasingly acknowledged, but delivery is generally uncommon. Reaching women for interconception care is potentially easier than for preconception care, however the concept is still unfamiliar. Expert consensus could facilitate guidelines, policies and subsequent implementation. A national and subsequent international expert meeting were organized to discuss the term, definition, content, relevant target groups, and ways to reach target groups for interconception care.Methods: We performed a literature study to develop propositions for discussion in a national expert meeting in the Netherlands in October 2015. The outcomes of this meeting were discussed during an international congress on preconception care in Sweden in February 2016. Both meetings were recorded, transcribed and subsequently reviewed by participants.Results: The experts argued that the term, definition, and content for interconception care should be in line with preconception care. They discussed that the target group for interconception care should be "all women who have been pregnant and could be pregnant in the future and their (possible) partners". In addition, they opted that any healthcare provider having contact with the target group should reach out and make every encounter a potential opportunity to promote interconception care.Discussion: Expert discussions led to a description of the term, definition, content, and relevant target groups for interconception care. Opportunities to reach the target group were identified, but should be further developed and evaluated in policies and guidelines to determine the optimal way to deliver interconception care.

Adverse pregnancy and perinatal outcome in patients with recurrent pregnancy loss: Multiple imputation analyses with propensity score adjustment applied to a large-scale birth cohort of the Japan Environment and Children's Study

PROBLEM

Several studies have reported the increased risk of preterm birth, premature rupture of membranes, and low birth weight in patients with recurrent pregnancy loss (RPL). There have been a limited number of large population-based studies examining adverse pregnancy and perinatal outcome after RPL. Multiple-imputed analyses (MIA) adjusting for biases due to missing data is also lacking.

METHOD OF STUDY

A nationwide birth cohort study known as the "Japan Environment and Children's Study (JECS)" was conducted by the Ministry of the Environment. The subjects consisted of 104 102 registered children (including fetuses or embryos).

RESULTS

No increased risk of a congenital anomaly, aneuploidy, neonatal asphyxia, or a small for date infant was observed among the children from women with a history of RPL. A novel increased risk of placental adhesion and uterine infection was found. The adjusted ORs using MIA in women with three or more PL were 1.76 (95% CI, 1.04-2.96) for a stillbirth, 1.68 (1.12-2.52) for a pregnancy loss, 2.53 (1.17-5.47) for placental adhesion, 1.87 (1.37-2.55) and 1.60 (.99-2.57) for mild and severe hypertensive disorders of pregnancy, respectively, 1.94 (1.06-3.55) for uterine infection, 1.28 (1.11-1.47) for caesarean section and .86 (.76-.98) for a male infant.

CONCLUSION

MIA better quantified the risk, which could encourage women who might hesitate to attempt a subsequent pregnancy.

Pregnancy before recurrent pregnancy loss more often complicated by post-term birth and perinatal death

INTRODUCTION

The cause of recurrent pregnancy loss often remains unknown. Possibly, pathophysiological pathways are shared with other pregnancy complications.

MATERIAL AND METHODS

All women with secondary recurrent pregnancy loss (SRPL) visiting Leiden University Medical Center (January 2000-2015) were included in this retrospective cohort to assess whether women with SRPL have a more complicated first pregnancy compared with control women. SRPL was defined as three or more consecutive pregnancy losses before 22 weeks of gestation, with a previous birth. The control group consisted of all Dutch nullipara delivering a singleton (January 2000-2015). Information was obtained from the Dutch Perinatal Registry. Outcomes were preeclampsia, preterm birth, post-term birth, intrauterine growth restriction, breach position, induction of labor, cesarean section, congenital abnormalities, perinatal death and severe hemorrhage in the first ongoing pregnancy. Subgroup analyses were performed for women with idiopathic SRPL and for women ≤35 years.

RESULTS

In all, 172 women with SRPL and 1 196 178 control women were included. Women with SRPL were older and had a higher body mass index; 29.7 years vs. 28.8 years and 25.1 kg/m² vs. 24.1 kg/m² , respectively. Women with SRPL more often had a post-term birth (OR 1.86, 95% CI 1.10-3.17) and more perinatal deaths occurred in women with SRPL compared with the control group (OR 5.03, 95% CI 2.48-10.2). Similar results were found in both subgroup analyses.

CONCLUSIONS

The first ongoing pregnancy of women with (idiopathic) SRPL is more often complicated by post-term birth and perinatal death. Revealing possible links between SRPL and these pregnancy complications might lead to a better understanding of underlying pathophysiology.

Two miscarriages, consecutive or non-consecutive, does it change something?

OBJECTIVES

To assess the rate of anomalies in the etiological evaluation of patients presenting recurrent early miscarriages (RM) according to miscarriage chronology (number of miscarriages, history of live birth and succession of RM).

METHODS

Retrospective single centre study including RM, defined as at least 2 miscarriages at less than 14 weeks of gestation (WG) between the 1st January 2012 and the 31st December 2015. Clinical data and etiological evaluation include blood glucose levels, screening for antiphospholipid syndrome (APS), endocrine assessment, vitamin levels, pelvic imaging, karyotyping of both partners, chronic endometritis and thrombophilia screening.

RESULTS

Two hundred and eighty-eight patients were included over this period, 118 (41%) patients had no history of live birth. Two hundred and twenty-three (77%) patients had consecutive RM and 65 (22%) patients had non-consecutive RM. For consecutive RM, 62,8% had thrombophilic disorders versus 69,8% for non-consecutive RM (P>0,05); 44,7% had endocrine disorders or vitamin deficiencies versus 39,7%; 34,6% of patients with consecutive RM had uterine anomalies versus 45,5% respectively. No difference was found depending on the recurrence of RM or the history of live birth (P>0.05) apart from the age of the patient. Fifty-nine (17.4%) patients had uterine anomalies. There are 24 chronic endometritis on 31 biospsies performed. Seventy-eight (27%) patients were offered treatment. Ninety-four (90%) patients showed good therapy compliance. Eighty-one (78%) patients became pregnant.

CONCLUSION

An etiological evaluation provides, for over half of the cases, an etiology or the identification of risk factors responsible for RM, as well as in some cases offering an adapted, efficient, therapeutic approach. This evaluation should be offered regardless of the obstetric history of the patient.

Adverse Pregnancy Outcomes of Patients with History of First-Trimester Recurrent Spontaneous Abortion

Although a history of first-trimester recurrent spontaneous abortion (FRSA) is regarded as a risk factor in antenatal care, the characteristic of subsequent pregnancy outcome is not clearly elucidated. Here, a retrospective analysis was performed on the clinical data of 492 singleton pregnant women. 164 of them with the history of FRSA were enrolled in study group, compared to 328 deliveries without the history of FRSA. For maternal outcomes, patients in the study group delivered earlier with mean gestational age and the incidences of cesarean section and postpartum hemorrhage were higher compared to the control group. For placental outcomes, the incidence of placenta-mediated pregnancy complications (PMPC) in the study group increased in terms of late-onset preeclampsia, oligohydramnios, early-onset fetal growth restriction, and second-trimester abortion. Patients in the study group were more likely to suffer from placenta accreta, placenta increta, and placenta percreta. For perinatal outcomes, the proportion of birth defects of newborns in the study group was greater. At last, logistic regression analyses showed that the history of FRSA was an independent risk factor for cesarean section and pregnancy complications. In conclusion, women with the history of FRSA are often exposed to an elevated incidence of maternal-placental-perinatal adverse pregnancy outcomes.

Maternal fetal loss history and increased acute leukemia subtype risk in subsequent offspring: a systematic review and meta-analysis

PURPOSE

History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0-14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted.

METHODS

Eligible studies (N = 32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken.

RESULTS

Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04-1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05-1.19) and for AML (OR 1.13, 95%CI 0.91-1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02-1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19-4.60).

CONCLUSIONS

In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.

Two-year outcome after recurrent first trimester miscarriages: prognostic value of the past obstetric history

PURPOSE

Recurrent miscarriage (RM) is a stressful condition which gives rise to extensive diagnostic evaluation and is seen as a potentially curable maternal disease. Nevertheless, epidemiological data have shown that outcome is related to fertility. In addition to maternal age and number of preceding miscarriages, further markers derived from the past history may support counselling.

METHODS

Observational trial comprising 228 couples who were referred between 1996 and 2003 for immunological evaluation at maternal ages 20-39 years after three or more spontaneously conceived primary first trimester miscarriages. They were interviewed in 2005, ongoing pregnancies were followed up until birth in 2006. Past obstetric history was correlated with 2 year cumulative pregnancy and delivery rates (CPR, CDR).

RESULTS

CPR and CDR were 206/228 (90.4 %) and 174/228 (76.4 %). Duration of infertility was associated with lower CPR (up to 3/>3 years, p < 0.01), whereas age and number of preceding losses inversely correlated with CDR (<35 years/35-39 years, p < 0.002; 3/>3 miscarriages, p < 0.002). Detection of an embryonic heart beat in 2-3 of the first three miscarriages resulted in favourable outcome (CPR: p < 0.02, CDR: p < 0.002). Prognosis was excellent in younger fertile women after three miscarriages where vital signs had been detected; under less favourable conditions not only risks for further miscarriage, but also for secondary infertility were elevated.

CONCLUSION

Secondary infertility is a feature of RM. Embryonic vital signs in preceding pregnancies are prognostic markers and should be regarded as a strong confounding factor in trials on therapeutic interventions. Prevention may be more appropriate than treatment.

Higher levels of procoagulant microparticles in women with recurrent miscarriage are not associated with antiphospholipid antibodies

STUDY QUESTION

Are the levels of circulating cell-derived microparticles (cMPs) in patients with recurrent miscarriage (RM) associated with the antiphospholipid syndrome (APS)?

SUMMARY ANSWER

cMPs in women with RM are not associated with antiphospholipid antibodies (aPLs).

WHAT IS KNOWN ALREADY

Previous studies have focused on cMP levels in RM patients. Most studies have shown higher levels of cMPs in RM patients whereas others have reported lower levels. Data regarding cMPs in patients with the APS are scanty in the literature.

STUDY DESIGN, SIZE, DURATION

A case-control study including three groups of patients. A total of 154 women were prospectively recruited from September 2009 to October 2013. Four patients refused to participate. The APS group consisted of 50 women that had been previously diagnosed with primary APS and had had ≥3 consecutive first trimester miscarriages. The uRM group included 52 couples with ≥3 consecutive first trimester miscarriages of unknown etiology. The fertile control (FER) group was composed of 52 healthy fertile women with no history of pregnancy losses. Miscarriage was defined as intrauterine pregnancy loss at <10 weeks' size on ultrasound.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Venous blood samples for coagulation studies and cMP determinations were obtained. All patients underwent a thrombophilia study.

MAIN RESULTS AND THE ROLE OF CHANCE

cMP levels were significantly higher in the APS and uRM groups versus the FER group (P < 0.0001 and P = 0.009, respectively) (cMP number × 10(3)/ml plasma [mean ± SD]: APS: 18.5 ± 13.6; uRM: 16.3 ± 13.8; FER: 9.7 ± 4.6). There were no statistically significant differences in cMP levels between the APS and uRM groups.

LIMITATIONS, REASONS FOR CAUTION

The sample size was arbitrarily decided according to previous studies analyzing cMPs in RM patients. Different cMP subtypes were not investigated.

WIDER IMPLICATIONS OF THE FINDINGS

The present study adds further data on the subject showing that patients with RM, irrespective of testing positive for aPLs, have increased levels of cMPs compared with healthy fertile controls. The presence of elevated cMPs in RM women may reflect an ongoing systemic pathological, albeit asymptomatic, status that can become deleterious in the setting of pregnancy.

STUDY FUNDING/COMPETING INTERESTS

This study was supported in part by grant from FIS-PI11/01560 within the 'Plan Nacional de I+D+I' and co-funded by the 'ISCIII-Subdirección General de Evaluación' and the 'Fondo Europeo de Desarrollo Regional (FEDER)'. The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

Not applicable.