Risk of recurrent stillbirth: a cohort study

Exposure to high dose of polystyrene nanoplastics causes trophoblast cell apoptosis and induces miscarriage

BACKGROUND

With rapid increase in the global use of various plastics, microplastics (MPs) and nanoplastics (NPs) pollution and their adverse health effects have attracted global attention. MPs have been detected out in human body and both MPs and NPs showed female reproductive toxicological effects in animal models. Miscarriage (abnormal early embryo loss), accounting for 15-25% pregnant women worldwide, greatly harms human reproduction. However, the adverse effects of NPs on miscarriage have never been explored.

RESULTS

In this study, we identified that polystyrene (PS) plastics particles were present in women villous tissues. Their levels were higher in villous tissues of unexplained recurrent miscarriage (RM) patients vs. healthy control (HC) group. Furthermore, mouse assays further confirmed that exposure to polystyrene nanoplastics (PS-NPs, 50 nm in diameter, 50 or 100 mg/kg) indeed induced miscarriage. In mechanism, PS-NPs exposure (50, 100, 150, or 200 µg/mL) increased oxidative stress, decreased mitochondrial membrane potential, and increased apoptosis in human trophoblast cells by activating Bcl-2/Cleaved-caspase-2/Cleaved-caspase-3 signaling through mitochondrial pathway. The alteration in this signaling was consistent in placental tissues of PS-NPs-exposed mouse model and in villous tissues of unexplained RM patients. Supplement with Bcl-2 could efficiently suppress apoptosis in PS-NPs-exposed trophoblast cells and reduce apoptosis and alleviate miscarriage in PS-NPs-exposed pregnant mouse model.

CONCLUSIONS

Exposure to PS-NPs activated Bcl-2/Cleaved-caspase-2/Cleaved-caspase-3, leading to excessive apoptosis in human trophoblast cells and in mice placental tissues, further inducing miscarriage.

Incidence of stillbirth among women with different risk profiles in Stockholm 2001-2020: a repeated cross-sectional study

INTRODUCTION

The incidence of stillbirth in Sweden has started to decline. However, some comparable high-income countries in Europe have an even lower incidence, indicating a potential for further reduction. The aim of our study was to investigate how the incidence of stillbirth for singleton pregnancies has changed over the past two decades in the Stockholm Region in different groups of women to detect the groups at highest risk.

MATERIAL AND METHODS

This was a repeated cross-sectional study with data from the Stockholm Stillbirth Database and the Pregnancy Register including all cases of stillbirth in Stockholm in singleton pregnancies between 2001 and 2020, in total 1804 stillbirths. The time period was divided into four equal groups and the incidence of stillbirth was compared between the groups.

RESULTS

The overall incidence of stillbirth in the Stockholm Region has decreased from 3.8/1000 births in 2001-2005 to 2.9/1000 births in 2016-2020 (P-value <0.001). In most of the groups studied, the incidence decreased, but among women originating from sub-Saharan Africa the incidence significantly rose from 7.9/1000 births in 2001-2005 to 10.1/1000 births in 2016-2020 (P-value 0.025). In this group, stillbirth occurred prematurely to a higher extent and the women were more likely to be multiparous.

CONCLUSIONS

The incidence of stillbirth in the Stockholm Region has declined. However, among women originating from sub-Saharan Africa the incidence was significantly higher compared with women originating from other regions and it is still rising. More research is needed to understand why this group is at higher risk and how to monitor their pregnancies to decrease this risk.

Intrauterine Fetal Death in Term Pregnancy-A Single Tertiary Clinic Study

INTRODUCTION

Intrauterine fetal death (IUFD) is defined as death of the fetus after the 20th week of gestation. Despite regular monitoring the incidence of IUFD remains high. This study aims to assess the incidence and maternal conditions associated with IUFD over term pregnancies in a twelve-year period.

MATERIALS AND METHODS

A retrospective descriptive study was conducted on a population of women in whom IUFD was diagnosed in a term pregnancy during the period from January 2010 to December 2022. The study was at the Clinic for Obstetrics and Gynecology, University Clinic Centre of Serbia. The analyses included the number of deliveries, live births, and stillbirths, as well as maternal, fetal, and placental conditions associated with the risk of IUDF. The statistical analysis involved descriptive statistical methods and one sample proportion.

RESULTS

The average age of the patients was 30 years. Most patients had secondary and higher education, and 70% of patients had regular pregnancy monitoring; 53.33% were primiparous and pregnancies occurred spontaneously. IUFD mainly occurred in the 39th week of gestation. In total, 38.3% had one to two associated diseases, 5% more than three, and 58.33% were healthy. Recurrence of IUFD was reported by 10% of patients, while 8.33% had a history of spontaneous abortion. Over 80% of placental histopathological findings indicated some pathology (e.g., infarction, infections, placental abruption).

CONCLUSIONS

The most significant risk factors for IUFD in term pregnancies in our population during the study period were hypertensive syndrome in pregnancy, obesity and gestational diabetes. Pathological findings on the placenta were more common in our study group than is usually reported with infractions of placental tissue being the most common, even in healthy women.

Risk factors for stillbirth at term: an Italian area-based, prospective cohort study

BACKGROUND

Stillbirth at term has great emotional impact on both parents and professionals. In developed countries, efforts to identify risk factors are mandatory to plan area-specific prevention strategies.

OBJECTIVE

The aim of the study was to identify independent risk factors that contribute to stillbirth at 37 weeks' gestation or later.

STUDY DESIGN

This was an area-based, prospective cohort study on pregnancy at term with enrolled from 2014 to 2021 in Emilia-Romagna, a north Italian region. Data were retrieved from both birth certificates and the Stillbirth Surveillance system database. To identify independent risk factors, a multivariate analysis using logistic regression was performed. A descriptive analysis of the causes of stillbirth is also reported.

RESULTS

In the observation period, 246,437 babies born at term (including 260 stillbirths, giving a rate of 1.06/1000) were considered. The risk factors independently associated with stillbirth were small for gestational age babies (odds ratio, 2.58; 95% confidence interval, 1.88-3.53), pregnancy achieved though fertility treatments (odds ratio, 2.01; 95% confidence interval, 1.15-3.51), and delayed access to pregnancy services (odds ratio, 1.56; 95% confidence interval, 1.10-2.22). In multipara, the presence of a previous stillbirth (odds ratio, 3.91; 95% confidence interval, 1.98-7.72) was also associated with an increased risk for recurrence. Early- rather than late-term was an additional risk factor. The most frequent causes of death were placental and cord disorders (61/260 and 56/260, respectively). However, 28.1% of cases remain unexplained.

CONCLUSION

The risks for stillbirth at term are known early in pregnancy or could be identified through tailored antenatal management, allowing effective preventive strategies to reduce preventable cases.

Stillbirth and neonatal mortality in a subsequent pregnancy following stillbirth: a population-based cohort study

BACKGROUND

A history of stillbirth is a risk factor for recurrent fetal death in a subsequent pregnancy. Reported risks of recurrent fetal death are often not stratified by gestational age. In subsequent pregnancies increased rates of medical interventions are reported without evidence of perinatal benefit. The aim of this study was to estimate gestational-age specific risks of recurrent stillbirth and to evaluate the effect of obstetrical management on perinatal outcome after previous stillbirth.

METHODS

A retrospective cohort study in the Netherlands was designed that included 252.827 women with two consecutive singleton pregnancies (1^st and 2^nd delivery) between 1999 and 2007. Data was obtained from the national Perinatal Registry and analyzed for pregnancy outcomes. Fetal deaths associated with a congenital anomaly were excluded. The primary outcome was the occurrence of stillbirth in the second pregnancy stratified by gestational age. Secondary outcome was the influence of obstetrical management on perinatal outcome in a subsequent pregnancy.

RESULTS

Of 252.827 first pregnancies, 2.058 pregnancies ended in a stillbirth (8.1 per 1000). After adjusting for confounding factors, women with a prior stillbirth have a two-fold higher risk of recurrence (aOR 1.96, 95% CI 1.07-3.60) compared to women with a live birth in their first pregnancy. The highest risk of recurrence occurred in the group of women with a stillbirth in early gestation between 22 and 28 weeks of gestation (a OR 2.25, 95% CI 0.62-8.15), while after 32 weeks the risk decreased. The risk of neonatal death after 34 weeks of gestation is higher in women with a history of stillbirth (aOR 6.48, 95% CI 2.61-16.1) and the risk of neonatal death increases with expectant obstetric management (aOR 10.0, 95% CI 2.43-41.1).

CONCLUSIONS

A history of stillbirth remains an important risk for recurrent stillbirth especially in early gestation (22-28 weeks). Women with a previous stillbirth should be counselled for elective induction in the subsequent pregnancy at 37-38 weeks of gestation to decrease the risk of perinatal death.