Placental pathology and maternal factors associated with stillbirth: An institutional based case-control study in Northern Tanzania

Decreased Alpha Klotho Expression in Placentas Exposed to Severe Maternal Vascular Malperfusion

BACKGROUND

Placental maternal vascular malperfusion (MVM) is characterized by accelerated villous maturation and has been associated with a decrease in the antiaging protein, alpha-klotho (AK). Our aim was to characterize AK protein and gene expression in the placenta and fetal organs.

METHODS

We utilized 2 cohorts. First, we characterized AK protein expression in an autopsy cohort where cases were defined as MVM as the cause of fetal death compared to a stillborn control population. Second, we characterized placental and umbilical cord blood AK gene expression in a liveborn population with and without MVM.

RESULTS

We found decreased protein expression in the villous trophoblastic cells of placentas exposed to severe MVM and decreased AK gene expression in placental tissue exposed to MVM. We did not see any statistically significant differences in fetal organ or umbilical cord blood AK expression based on the presence or absence of MVM. Furthermore, in liveborn infants, we also found increased odds of preterm birth with lower placental AK expression.

CONCLUSIONS

Decreased AK gene and protein expression in the placenta in the setting of MVM is consistent with the theory of placental aging in MVM and is associated with increased odds of preterm birth.

The effect of maternal age on still birth in Africa: A systematic review and meta-analysis

Background and Aims

Stillbirth is a public health as well as a development problem in low and middle-income countries. The studies that found out maternal age as a factor for the risk of stillbirth reported different findings. This systematic review and meta-analysis is believed to fill the inconclusiveness of these findings. Hence, the aim of this systematic review and meta-analysis is to estimate the pooled effect of advanced maternal age on stillbirth in Africa.

Methods

PubMed & HINARY databases and Google Scholar search engine were searched to access the primary studies. The extracted data using Microsoft excel was exported to Stata 15 software for analysis. The presence of heterogeneity was checked using Cochran's Q statistic and the I 2 test. Publication bias was examined by using funnel plot and Egger's test. The pooled effect measure with DerSimonian and Laird method of random-effect model was reported using odds ratio (OR) with respective 95% confidence interval.

Results

Totally, 14 articles are included for the systematic review and meta-analysis. The stillbirth reported by the studies ranges from 15 to 146.7 per 1000 births. The overall OR of advanced maternal age (≥35 years) on stillbirth is 1.42 (1.18, 1.71) when compared with the age group of 20-35 years. The cumulative effect of getting pregnant at advanced age on stillbirth was slightly increasing from year to year.

Conclusion

Advanced maternal age is a risk factor for stillbirth. Health Information Communication on the risk of getting pregnant at the advanced ages on stillbirth should be well addressed to all women of reproductive age group.

Stillbirth rates and their determinants in a national maternity hospital in Phnom Penh, Cambodia in 2017-2020: a cross-sectional assessment with a nested case-control study

BACKGROUND

In Cambodia, stillbirths and their underlying factors have not been systematically studied. This study aimed to assess the proportion and trends in stillbirths between 2017 and 2020 in a large maternity referral hospital in the country and identify their key determinants to inform future prevention efforts.

METHODS

This was a retrospective cross-sectional analysis with a nested case-control study of women giving birth at the National Maternal and Child Health Centre (NMCHC) in Phnom Penh, 2017-2020. We calculated percentages of singleton births at ≥ 22 weeks' gestation resulting in stillbirth and annual stillbirth rates by timing: intrapartum (fresh) or antepartum (macerated). Multivariable logistic regression was used to explore factors associated with stillbirth, where cases were all women who gave birth to a singleton stillborn baby in the 4-year period. One singleton live birth immediately following each case served as an unmatched control. Multiple imputation was used to handle missing data for gestational age.

RESULTS

Between 2017 and 2020, 3.2% of singleton births ended in stillbirth (938/29,742). The stillbirth rate increased from 24.8 per 1000 births in 2017 to 38.1 per 1000 births in 2020, largely due to an increase in intrapartum stillbirth rates which rose from 18.8 to 27.4 per 1000 births in the same period. The case-control study included 938 cases (stillbirth) and 938 controls (livebirths). Factors independently associated with stillbirth were maternal age ≥ 35 years compared to < 20 years (aOR: 1.82, 95%CI: 1.39, 2.38), extreme (aOR: 3.29, 95%CI: 2.37, 4.55) or moderate (aOR: 2.45, 95%CI: 1.74, 3.46) prematurity compared with full term, and small-for-gestational age (SGA) (aOR: 2.32, 1.71, 3.14) compared to average size-for-age. Breech/transverse births had nearly four times greater odds of stillbirth (aOR: 3.84, 95%CI: 2.78, 5.29), while caesarean section reduced the odds by half compared with vaginal birth (aOR: 0.50, 95%CI: 0.39, 0.64). A history of abnormal vaginal discharge increased odds of stillbirth (aOR: 1.42, 95%CI: 1.11, 1.81) as did a history of stillbirth (aOR: 3.08, 95%CI: 1.5, 6.5).

CONCLUSIONS

Stillbirth prevention in this maternity referral hospital in Cambodia requires strengthening preterm birth detection and management of SGA, intrapartum care, monitoring women with stillbirth history, management of breech births, and further investigation of high-risk referral cases.

Timing of perinatal death; causes, circumstances, and regional variations among reviewed deaths in Ethiopia

INTRODUCTION

Ethiopia is one of the countries facing a very high burden of perinatal death in the world. Despite taking several measures to reduce the burden of stillbirth, the pace of decline was not that satisfactory. Although limited perinatal mortality studies were conducted at a national level, none of the studies stressed the timing of perinatal death. Thus, this study is aimed at determining the magnitude and risk factors that are associated with the timing of perinatal death in Ethiopia.

METHODS

National perinatal death surveillance data were used in the study. A total of 3814 reviewed perinatal deaths were included in the study. Multilevel multinomial analysis was employed to examine factors associated with the timing of perinatal death in Ethiopia. The final model was reported through the adjusted relative risk ratio with its 95% Confidence Interval, and variables with a p-value less than 0.05 were declared statistically significant predictors of the timing of perinatal death. Finally, a multi-group analysis was carried out to observe inter-regional variation among selected predictors.

RESULT

Among the reviewed perinatal deaths, 62.8% occurred during the neonatal period followed by intrapartum stillbirth, unknown time of stillbirth, and antepartum stillbirth, each contributing 17.5%,14.3%, and 5.4% of perinatal deaths, respectively. Maternal age, place of delivery, maternal health condition, antennal visit, maternal education, cause of death (infection and congenital and chromosomal abnormalities), and delay to decide to seek care were individual-level factors significantly associated with the timing of perinatal death. While delay reaching a health facility, delay to receive optimal care health facility, type of health facility and type region were provincial-level factors correlated with the timing of perinatal death. A statistically significant inter-regional variation was observed due to infection and congenital anomalies in determining the timing of perinatal death.

CONCLUSION

Six out of ten perinatal deaths occurred during the neonatal period, and the timing of perinatal death was determined by neonatal, maternal, and facility factors. As a way forward, a concerted effort is needed to improve the community awareness of institutional delivery and ANC visit. Moreover, strengthening the facility level readiness in availing quality service through all paths of the continuum of care with special attention to the lower-level facilities and selected poor-performing regions is mandatory.

Placental findings in singleton stillbirths: a case-control study from a tertiary-care center in India

OBJECTIVES

Placental examination in a case of stillbirth can provide insight into causative/associated factors with fetal demise. The aim of this study was to compare placental and umbilical cord pathologies in singleton stillbirth and livebirth placentas, and to find prevalence of various associated maternal and fetal clinical factors.

METHODS

This case-control study was conducted at a tertiary-care center in India over a period of 20 months. About 250 women who delivered stillborn fetus ≥28 weeks' gestation and 250 maternal-age-matched controls were recruited. Sociodemographic and clinical details were noted and placental gross and microscopic examination was done. Placental findings were compared between stillbirth and livebirth (overall), preterm stillbirth and preterm livebirth as well as term stillbirth and term livebirth in six categories - placenta gross, cord gross, membranes gross, maternal vascular malperfusion, fetal vascular malperfusion and inflammatory response. Prevalence of 11 maternal and fetal factors were studied in all categories of placental findings in both livebirth and stillbirth.

RESULTS

Placental findings in all six categories were significantly associated with stillbirths (p<0.05). The placental findings associated with stillbirth with highest odds included placental hypoplasia (OR 9.77, 95% CI 5.46-17.46), necrotizing chorioamnionitis (OR 9.30, 95% CI 1.17-73.96) and avascular villi (OR 8.45, 95% CI 3.53-20.25). More than half of the women with stillbirths had medical disorders (n=130, 52.0%) and the most prevalent was hypertensive disorder (n=45, 18.0%).

CONCLUSIONS

Changes in placenta are associated with development of stillbirth. Therefore, antenatal investigations to identify placental dysfunction should be investigated to determine whether these reduce stillbirth. Also, placental examination in a case of stillbirth can detect/diagnose many maternal/fetal conditions and thereby can help in preventing future stillbirths.

Building Perinatal Pathology Research Capacity in Sub-Saharan Africa

Introduction

Over two million stillbirths and neonatal deaths occur in sub-Saharan Africa (sSA) annually. Despite multilateral efforts, reducing perinatal mortality has been slow. Although targeted pathologic investigation can often determine the cause of perinatal death, in resource-limited settings, stillbirths, early neonatal deaths, and placentas are rarely examined pathologically. However, the placenta is a key source of diagnostic information and is the main determinant of fetal growth and development in utero, influencing child health outcomes.

Methods

In 2016, our collaborative intercontinental group began investigating infectious perinatal death and adverse child health outcomes in Uganda. We developed and initiated a 4-day combined didactic/practical curriculum to train health workers in placental collection, gross placental examination, and tissue sampling for histology. We also trained a local technician to perform immunohistochemistry staining.

Results

Overall, we trained 12 health workers who performed gross placental assessment for > 1,000 placentas, obtaining > 5,000 formalin-fixed tissue samples for research diagnostic use. Median placental weights ranged from 425 to 456 g, and 33.3% of placentas were < 10th percentile in weight, corrected for gestational age. Acute chorioamnionitis (32.3%) and maternal vascular malperfusion (25.4%) were common diagnoses.

Discussion

Through a targeted training program, we built capacity at a university-affiliated hospital in sSA to independently perform placental collection, gross pathologic examination, and placental tissue processing for histology and special stains. Our training model can be applied to other collaborative research endeavors in diverse resource-limited settings to improve research and clinical capacity and competency for diagnostics and management of stillbirth, neonatal death, and child health outcomes.

Histopathological examination of the placenta after delivery in pregnant women with COVID-19

Introduction: COVID-19 is a viral disease generated by a new coronavirus named SARS-CoV-2. The consequences of this virus on the human placenta and the newborn are still unclear. IL-6 can disturb the placenta's immunological homeostasis and be employed as an inflammatory marker for the poor prognosis of COVID-19 infection. Bax has some features like being a key protein regulating apoptotic mechanisms and plays an important role in both maintaining dynamic balance and integrity in the placenta as in many tissues. This study aims to indicate the impact of COVID-19 on inflammation and apoptotic pathways in the placenta by using IL-6 and Bax antibodies. Material and Method: COVID-19 positive (n:10) and COVID-19 negative (n:10) normotensive placentas were included. Haematoxylin-eosin staining and immunohistochemical staining (IL-6 and Bax antibodies) were applied. Statistical data of immunohistochemical (IL-6 and Bax expression) staining results were assessed by analyzing the H-score. Biochemical parameters were recorded. Group means were analyzed with a nonparametric Kruskal Wallis Test. Results: In the COVID-19 group, increased syncytial knots, fibrin deposition, inflammation, fibrinoid necrosis, neutrophil accumulation were observed. The COVID-19 group had considerably higher levels of IL-6 and Bax expression than the control group. Furthermore, COVID-19 patients had statistically lower WBC and higher CRP values than normotensive patients. Conclusion: COVID-19 has been linked to placental inflammation and trophoblast cell damage, both of which can result in major maternal and fetal problems during pregnancy. We found intense IL-6 expression in the placentas of pregnant women with COVID-19 infection. A rise in IL-6 levels triggers CRP production, and this increase is linked to the severity of COVID-19 as a risk factor. Also, we suggested that COVID-19 infection triggers the apoptotic process in placental tissue by increasing the expression of the proapoptotic Bax protein. It is clinically very significant to follow up COVID-19 positive pregnancies for maternal and fetal health. During this follow-up, IL-6 and Bax expression levels in the placenta, together with histopathological findings and serum CRP levels, can guide the evaluation of the prognosis, severity and response to treatment of the disease.

The effect of inter-pregnancy interval on stillbirth in urban South Ethiopia: a community-based prospective cohort study

BACKGROUND

Stillbirth is an invisible and poorly understood adverse pregnancy outcome that remains a challenge in clinical practice in low-resource settings. It is also a key concern in Ethiopia where more than half of pregnancies occur shortly after preceding childbirth. Whether the interval between pregnancies has an effect on stillbirth or not is unclear. Therefore, we aimed to assess the effect of inter-pregnancy interval on stillbirth in urban South Ethiopia.

METHODS

A community-based prospective cohort study was conducted among 2578 pregnant women and followed until delivery. Baseline data were collected at the household level during registration and enrolment. End-line data were collected from hospitals during delivery. Exposed groups were pregnant women with inter-pregnancy intervals < 18 months and 18-23 months. Unexposed group contains women with inter-pregnancy intervals 24-60 months. A generalized linear model for binary outcome was applied, using R version 4.0.5 software. Relative risk (RR) was used to estimate the effect size with a 95% confidence level. Attributable fraction (AF) and population attributable fraction (PAF) were used to report the public health impact of exposure.

RESULTS

The overall incidence of stillbirth was 15 per 1000 total births, (95% CI: 11, 20%). However, the incidence was varied across months of inter-pregnancy intervals; 30 (< 18 months), 8 (18-23 months) and 10 (24-60 months) per 1000 total births. The risk of stillbirth was nearly four times (ARR = 3.55, 95%CI: 1.64, 7.68) higher for women with inter-pregnancy interval < 18 months as compared to 24-60 months. This means, about 72% (AF = 72, 95%CI: 39, 87%) of stillbirth among the exposed group (inter-pregnancy interval < 18 months category) and 42% (PAF = 42, 95%CI: 23, 50%) of stillbirth in the study population were attributed to inter-pregnancy interval < 18 months. These could be prevented with an inter-pregnancy interval that is at least 18 months or longer.

CONCLUSIONS

Inter-pregnancy interval under 18 months increases the risk of stillbirth in this population in urban South Ethiopia. Interventions targeting factors contributing to short inter-pregnancy intervals could help in reducing the risk of stillbirth. Improving contraceptive utilization in the community could be one of these interventions.