The risk of placental abruption and placenta previa in pregnant women with chronic hepatitis B viral infection: a systematic review and meta-analysis

Hepatitis B virus infection, infertility, and assisted reproduction

BACKGROUND: Hepatitis B virus (HBV) is one of the most widespread viruses worldwide and a major cause of hepatitis, cirrhosis, and hepatocellular carcinoma. Previous studies have revealed the impacts of HBV infection on fertility. An increasing number of infertile couples with chronic hepatitis B (CHB) virus infection choose assisted reproductive technology (ART) to meet their fertility needs. Despite the high prevalence of HBV, the effects of HBV infection on assisted reproduction treatment remain limited and contradictory. OBJECTIVE: The aim of this study was to provide a comprehensive overview of the effect of HBV infection on fertility and discuss its effects on pregnancy outcomes, vertical transmission, pregnancy complications, and viral activity during ART treatment. METHODS: We conducted a literature search in PubMed for studies on HBV infection and ART published from 1996 to 2022. RESULTS: HBV infection negatively affected fertility in both males and females. Existing research shows that HBV infection may increase the risk of pregnancy complications in couples undergoing assisted reproduction treatment. The impact of HBV infection on the pregnancy outcomes of ART is still controversial. Current evidence does not support that ART increases the risk of vertical transmission of HBV, while relevant studies are limited. With the development of ART, the risk of HBV reactivation (HBVr) is increasing, especially due to the wide application of immunosuppressive therapy. CONCLUSIONS: Regular HBV infection screening and HBVr risk stratification and management are essential to prevent HBVr during ART. The determination of optimal strategy and timing of prophylactic anti-HBV therapy during ART still needs further investigation.

Factors and outcomes for placental anomalies: An umbrella review of systematic reviews and meta-analyses

Background

Placental anomalies, including placenta previa (PP), placenta accreta spectrum disorders (PAS), and vase previa (VP), are associated with several adverse foetal-neonatal and maternal complications. However, there is still a lack of robust evidence on the pathogenesis and adverse outcomes of the diseases. Through this umbrella review, we aimed to systematically review existing meta-analyses exploring the factors and outcomes for pregnancy women with placental anomalies.

Methods

We searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to February 2023. We used AMSTAR 2 to assess the quality of the reviews and estimated the pooled risk and 95% confidence intervals (CIs) for each meta-analysis.

Results

We included 34 meta-analyses and extracted 55 factors (27 for PP, 22 for PAS, and 6 for VP) and 16 outcomes (12 for PP, and 4 for VP) to assess their credibility. Seven factors (maternal cocaine use (for PP), uterine leiomyoma (for PP), prior abortion (spontaneous) (PP), threatened miscarriage (PP), maternal obesity (PP), maternal smoking (PAS), male foetus (PAS)) had high epidemiological evidence. Twelve factors and six outcomes had moderate epidemiological evidence. Twenty-two factors and eight outcomes showed significant association, but with weak credibility.

Conclusions

We found varying levels of evidence for placental anomalies of different factors and outcomes in this umbrella review.

Registration

PROSPERO: CRD42022300160.

Maternal-to-Child Transmission of Hepatitis B Virus and Hepatitis Delta Virus

Maternal-to-child transmission of hepatitis B virus (HBV) and hepatitis delta virus (HDV) can lead to the risk of progressive liver disease in infants, but fortunately effective interventions exist to decrease transmission. Counseling on the risk of maternal-to-child transmission, care pathways to decrease transmission, and the implications of HBV and HDV on pregnancy outcomes are the key components of caring for pregnant people living with HBV and HDV.

Viral Infections During Pregnancy: The Big Challenge Threatening Maternal and Fetal Health

Viral infections during pregnancy are associated with adverse pregnancy outcomes, including maternal and fetal mortality, pregnancy loss, premature labor, and congenital anomalies. Mammalian gestation encounters an immunological paradox wherein the placenta balances the tolerance of an allogeneic fetus with protection against pathogens. Viruses cannot easily transmit from mother to fetus due to physical and immunological barriers at the maternal-fetal interface posing a restricted threat to the fetus and newborns. Despite this, the unknown strategies utilized by certain viruses could weaken the placental barrier to trigger severe maternal and fetal health issues especially through vertical transmission, which was not fully understood until now. In this review, we summarize diverse aspects of the major viral infections relevant to pregnancy, including the characteristics of pathogenesis, related maternal-fetal complications, and the underlying molecular and cellular mechanisms of vertical transmission. We highlight the fundamental signatures of complex placental defense mechanisms, which will prepare us to fight the next emerging and re-emerging infectious disease in the pregnancy population.

Significantly Low Levels of IgG Antibodies Against Oncogenic Merkel Cell Polyomavirus in Sera From Females Affected by Spontaneous Abortion

Merkel cell polyomavirus (MCPyV) is a small DNA tumor virus ubiquitous in humans. MCPyV establishes a clinically asymptomatic lifelong infection in healthy immunocompetent individuals. Viral infections are considered to be risk factors for spontaneous abortion (SA), which is the most common adverse complication of pregnancy. The role of MCPyV in SA remains undetermined. Herein, the impact of MCPyV infection in females affected by SA was investigated. Specifically, an indirect enzyme-linked immunosorbent assay (ELISA) method with two linear synthetic peptides/mimotopes mimicking MCPyV antigens was used to investigate immunoglobulin G (IgG) antibodies against MCPyV in sera from 94 females affected by SA [mean ± standard deviation (SD) age 35 ± (6) years] and from 96 healthy females undergoing voluntary pregnancy interruption [VI, mean (±SD) age 32 ± (7) years]. MCPyV seroprevalence and serological profiles were analyzed. The overall prevalence of serum IgG antibodies against MCPyV was 35.1% (33/94) and 37.5% (36/96) in SA and VI females, respectively (p > 0.05). Notably, serological profile analyses indicated lower optical densities (ODs) in females with SA compared to those undergoing VI (p < 0.05), thus indicating a reduced IgG antibody response in SA females. Circulating IgGs were identified in sera from SA and VI females. Our immunological findings indicate that a relatively reduced fraction of pregnant females carry serum anti-MCPyV IgG antibodies, while SA females presented a more pronounced decrease in IgG antibody response to MCPyV. Although yet to be determined, this immunological decrease might prompt an increase in MCPyV multiplication events in females experiencing abortive events. The role of MCPyV in SA, if present, remains to be determined.

Obstetric implications of maternal chronic hepatitis B virus infection

Antenatal screening for hepatitis B surface antigen seropositivity is widely adopted to identify pregnant women with chronic hepatitis B virus (HBV) infection in order to target their newborn infants for combined passive-active neonatal immunization to prevent the maternal-to-child transmission of HBV. It is less certain whether the presence of chronic HBV infection in these largely asymptomatic women could impact their pregnancy outcome. There is now gathering information in the literature, though sometimes conflicting, on the obstetric implications of chronic HBV infection. The conflicting data is most probably related to confounding factors such as the immunological phase of chronic HBV infection, viral genotype and activity, presence of hepatic inflammation and other co-existing liver disorders such as non-alcoholic fatty liver disease, and coinfection with other virus such as hepatitis C virus and micro-organisms, which are usually not examined, but which could have made significant influence on the occurrence of many of the pregnancy complications and adverse fetal and neonatal outcome. For pregnancy complications, the evidence suggests association with increased gestational diabetes mellitus, preterm birth, intrahepatic cholestasis of pregnancy, caesarean delivery, and postpartum haemorrhage, probably increased placental abruption and prelabour rupture of the membranes, and no effect or a reduction in the hypertensive disorders of pregnancy, especially preeclampsia. For perinatal outcome, there may be increased miscarriage and fetal malformations, and increase in both low birthweight and large-for-gestational age/macrosomic infants, as well as increased intrauterine fetal demise/stillbirth and fetal distress. However, most studies have not elaborated on the mechanisms or explanations of many of the adverse outcomes. Taken together, maternal chronic HBV infection increases the risk of adverse obstetric outcome overall, but further prospective studies are warranted to elucidate the reasons and mechanisms of, and with a view to mitigate, these adverse obstetric outcomes.

The effects of hepatitis B virus infection on natural and IVF pregnancy: A meta-analysis study

BACKGROUND

Hepatitis B virus (HBV) has been considered a significant cause of human reproductive failure in different studies; however, there is a considerable disagreement on the true impacts of HBV on female reproduction. This study has evaluated the impact of HBV infection on pregnancy complications in natural pregnancy and also on pregnancy outcomes in women undergoing in vitro fertilization (IVF) treatment.

METHOD

We searched Embase, Web of Science, PubMed and Google Scholar databases to identify the potentially relevant studies. Summary odds ratio (OR) or standardized mean difference (SMD) with 95% confidence interval (CI) was applied to assess the relationship. Heterogeneity testing, sensitivity analysis and publication bias testing were also performed.

RESULTS

A total of 42 studies concerning the effect of HBV infection on the natural and IVF pregnancy were included in this study. Our meta-analysis results revealed that HBV infection had a positive correlation to gestational diabetes mellitus (GDM) [OR = 1.32 (1.17-1.48) (p < 0.01)] and preterm birth [OR = 1.26 (1.14-1.40) (p < 0.01)] in natural pregnancy; however, HBV infection was not significantly associated with decreased fertility rates among the patients who underwent IVF.

CONCLUSION

This study revealed a strong association of GDM and preterm birth with higher rates of HBV infection in pregnant women. Also, our results suggested that HBV infection in patients undergoing IVF may not negatively influence the pregnancy outcome. It may be rational to conclude that IVF might be rather a safe and effective method for HBV+ females who desire to have children.

Hepatitis B Virus Infection in Pregnancy: Immunological Response, Natural Course and Pregnancy Outcomes

This review aimed to provide an update on the impact of pregnancy on the natural course of hepatitis B virus (HBV) infection and also on the impact of HBV infection on adverse pregnancy outcomes, including mother-to-child transmission (MTCT). For the literature review, original research articles, review articles, and guidelines were narratively reviewed and comprehensively validated. The databases of PubMed, EMBASE, and CINAHL were carefully searched for articles in English on topics related to HBV infection, pregnancy, and vertical transmission from 1960 to May 2021. Immunological changes during pregnancy such as suppression of Th1 response and induction of Th2 immunity lead to an impaired immune reaction to HBV and stimulate viral activity along with the reduction of CD8 T cells to escape immune detection. The impact of pregnancy on the natural course of chronic HBV infection seems to be minimal, while pregnancy can increase morbidity and mortality in the case of advanced HBV hepatitis or cirrhosis. Importantly, hepatitis flare or alanine aminotransferase (ALT) flare can occur during pregnancy and is more common during the postpartum period due to the interaction between HBV and the immune response. Interestingly, the impact of HBV infection on adverse pregnancy outcomes is more serious than ever thought. Updated evidence indicates that pregnancies with chronic HBV infection increase the risk of preterm birth and gestational diabetes, especially in cases of positive hepatitis e antigen (HBeAg).

Impact of maternal infection with hepatitis B virus on pregnancy complications and neonatal outcomes for women undergoing assisted reproductive technology treatment: A population-based study

The aim of this study was to investigate the impact of maternal hepatitis B virus (HBV) status on pregnancy complications and neonatal outcomes for women undergoing assisted reproductive technology (ART). A total of 7,011 pregnancies achieved by ART were included from a population-based database involving 523,111 pregnancies. Exposures of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) among pregnant women were routinely tested at the first antenatal visit for all pregnancies. We collected pregnancy complications (e.g., gestational diabetes mellitus [GDM], intrahepatic cholestasis of pregnancy [ICP]), neonatal outcomes and confounding variables from the same database. Univariate and multivariate analyses by adjusting confounders were conducted to evaluate the impact of maternal HBV infection. Prevalence of HBsAg seropositivity (HBsAg+) was 11.34% (95% CI 10.6-12.1) and that of HBsAg and HBeAg co-seropositivity (HBsAg+HBeAg+) was 2.55% (2.1-3.0) among included population. Compared with HBsAg-group, ICP risk in the HBsAg+group was higher (4.03% vs. 1.79%; adjusted odds ratio [aOR] 2.49, 1.65-3.77). Similarly, ICP prevalence in the HBsAg+HBeAg+ group was higher than that in the HBsAg-HBeAg- group (6.47% vs. 1.61%; aOR 4.78, 2.28-9.98). No associations were found between maternal HBV infection (i.e., HBsAg+, HBsAg+HBeAg+, or HBsAg+HBeAg-) and other adverse outcomes for women undergoing ART (i.e., GDM, pre-eclampsia, placental previa, premature separation of placenta, premature rupture of membranes, preterm birth and low birthweight) in this study. In conclusion, maternal HBV infection (HBsAg+or HBsAg+HBeAg+) probably increase ICP risk, but may not associate with other pregnancy complications or neonatal outcomes for pregnant women who underwent ART.

Impact of SARS-CoV-2 on the clinical outcomes and placental pathology of pregnant women and their infants: A systematic review

Pregnant women are susceptible to viral infections due to physiological changes such as cell-mediated immunity. No severe adverse pregnancy or neonatal outcomes have been consistently reported in 2019 novel coronavirus disease (COVID-19) positive pregnancy cases. There are controversies around the role of COVID-19 in pregnancy. A systematic review was conducted to examine clinical maternal and neonatal clinical outcomes. Studies were included if they reported SARS-CoV-2 infection among pregnant women and/or COVID-19 positive neonates as validated by positive antibody testing or viral testing using polymerase chain reaction. Case series, case reports, case-control studies, and comparative studies were included. Eight hundred and thirty-seven records were identified, resulting in 525 records for level I screening. Forty-one were included after full-text review. Results suggest elevated rates of intensive care unit (ICU) admission, gestational diabetes, preeclampsia, C-sections, pre-term birth, and C-reactive protein (CRP) in comparison to pregnant women without SARS-CoV-2. Careful monitoring of pregnancies with SARS-CoV-2 is recommended.

Maternal HBsAg carriers and pregnancy outcomes: a retrospective cohort analysis of 85,190 pregnancies

Background

Nowadays, a positive HBV carrier status is common among pregnant women, especially in endemic areas (such as China), little is known about the impact of maternal HBV infection on the risk of adverse pregnancy outcomes. Pregnant women with HBV infection often develop obstetric complications, such as pregnancy-induced hypertension (PIH) syndrome, postpartum hemorrhage, and gestational diabetes mellitus (GDM), and their infants often exhibit neonatal complications.

Methods

This study undertook a retrospective cohort analysis to explore the association of HBV carrier status with adverse pregnancy outcomes. A cohort of 85,190 women including 9699 HBsAg-positive and 73,076 HBsAg-negative pregnancies was retrospectively analyzed.

Results

It’s found that HBsAg-positive pregnancies may result in higher risk of various maternal outcomes such as ICP (OR 3.4,95%CI 2.80 to 4.13), postpartum hemorrhage (OR 1.16,95%CI 1.00 to 1.34). Interestingly, there was a decreased risk of Preeclampsia (OR 0.91,95%CI 0.87 to 0.96), premature rupture of membrane (OR 0.91,95%CI 0.87 to 0.96) and gestational hypertension (OR 0.828,95%CI 0.701 to 0.978). And in vaginal delivery subgroup analysis, It’s found that the HBsAg-positive group had a higher risk of placental abruption (OR, 1.44; 95% CI, 1.16–1.79).

Conclusions

The present results suggest that compared with HBV positive pregnancies were more likely to be ICP and postpartum hemorrhage. HBV-positive pregnant women underwent vaginal delivery were more likely to have placental abruption and premature birth compared with HBV-negative women. Obstetricians should be aware of ICP, postpartum hemorrhage, placental abruption and premature birth in HBV-positive pregnant women.

Acute-on-Chronic Liver Failure in Pregnant Patients with Chronic Hepatitis B: A Retrospective Observational Case Series Study

BACKGROUND AND AIMS

Acute-on-chronic liver failure (ACLF) is common in patients with end-stage liver disease and chronic hepatitis B (CHB) or hepatitis B virus- (HBV-) related cirrhosis. To date, no uniform definition and management strategy are available for ACLF. Although a considerable number of studies on ACLF has been published, there are few reports on ACLF in pregnant women with CHB. This study retrospectively reviewed five patients who were diagnosed with ACLF during pregnancy in the past 10 years. We aimed at investigating their clinical characteristics, treatment, biochemical test results, and maternal and fetal outcomes.

RESULTS

Asthenia, anorexia, and jaundice were the main initial clinical manifestations in these patients during the second or third trimester of pregnancy. All patients received antiviral therapy. None of the pregnant women died after treatment. Patient #4 was treated with an artificial liver support system, and patients #2 and #5 underwent transfusion therapy. The acute insult in all patients was HBV DNA reactivation. Except for patient #3, who chose an actively induced vaginal delivery because of intrauterine fetal demise, the remaining four patients underwent a preterm delivery via a cesarean section. The four neonates were alive, although all were small for gestational age.

CONCLUSION

Asthenia, anorexia, and jaundice during mid-late pregnancy should be immediately investigated. Before and during the pregnancy, hepatologists or obstetricians should actively screen pregnant women with CHB for HBV DNA status and alanine aminotransferase levels. Reactivation of HBV replication in pregnant women with CHB may lead to ACLF, especially in multiparous women. Once ACLF is diagnosed, antiviral therapy should be considered as soon as possible to protect maternal and fetal health.

Hepatitis B - chronic carrier status and pregnancy outcomes: An obstetric perspective

Antenatal screening for hepatitis B surface antigen (HBsAg) only identifies women with hepatitis B virus (HBV) infection for neonatal immunoprophylaxis. It does not reflect the phase of chronic infection, viral genotype and activity, hepatic inflammation, or other co-existing liver disorders. Coinfection with other viruses and micro-organisms may also be present. These factors in various combinations can impact pregnancy outcomes, and they are probably responsible for the conflicting literature on this issue. Pregnancy complications may interact with maternal HBV infection and hepatitis flares, leading to serious and lethal complications. Hepatitis flares are common especially postpartum, and they are unpredictable and unpreventable with antiviral treatment. Evidence on the association between HBsAg seropositivity with gestational diabetes mellitus, preterm birth, increased foetal growth, and reduced pregnancy hypertensive disorders is stronger than other adverse pregnancy outcomes. Baseline assessment of liver function, and viral markers and activity, can delineate the truly high-risk pregnancies for close monitoring.

Maternal Hepatitis B Infection Burden, Comorbidity and Pregnancy Outcome in a Low-Income Population on the Myanmar-Thailand Border: A Retrospective Cohort Study

Objectives

Hepatitis B virus (HBV) was believed to have minimal impact on pregnancy outcomes apart from the risk of perinatal transmission. In more recent years, there have been reports of adverse associations, most consistently preterm birth (PTB), but this is in the context of high rates of caesarean section. The aim of this study was to explore the association of HBV on pregnancy outcomes in marginalized, low-income populations on the Myanmar-Thailand border.

Methods

HBsAg positive (+) point of care rapid detection tests results were confirmed by immunoassays. Women with a confirmed HBsAg status, HIV- and syphilis-negative at first antenatal care screening, singleton fetus and known pregnancy outcome (Aug-2012 to Dec-2016) were included. Logistic regression analysis was used to evaluate associations between HBV group (controls HBsAg negative, HBsAg+/HBeAg-, or HBsAg+/HBeAg+) and pregnancy outcome and comorbidity.

Results

Most women were tested, 15,046/15,114 (99.6%) for HBV. The inclusion criteria were not met for 4,089/15,046 (27.2%) women due mainly to unavailability of pregnancy outcome and nonconfirmation of HBsAg+. In evaluable women 687/11,025 (6.2%) were HBsAg+, with 476/11,025 (4.3%) HBsAg+/HBeAg- and 211/11,025 (1.9%) were HBsAg+/HBeAg+. The caesarean section rate was low at 522/8,963 (5.8%). No significant associations were observed between pregnancy comorbidities or adverse pregnancy outcomes and HBV status.

Conclusions

The results highlight the disease burden of HBV in women on the Myanmar-Thailand border and support original reports of a lack of significant associations with HBsAg+ irrespective of HBeAg status, for comorbidity, and pregnancy outcomes in deliveries supervised by skilled birth attendants.

Current evidence on the management of hepatitis B in pregnancy

Hepatitis B virus (HBV) infection is one of the main public health problems across the globe, since almost one third of the world population presents serological markers of contact with the virus. A profound impact on the epidemiology has been exerted by universal vaccination programmes in many countries, nevertheless the infection is still widespread also in its active form. In the areas of high endemicity (prevalence of hepatitis B surface antigen positivity > 7%), mother-to-child transmission represents the main modality of infection spread. That makes the correct management of HBV in pregnancy a matter of utmost importance. Furthermore, the infection in pregnancy needs to be carefully assessed and handled not only with respect to the risk of vertical transmission but also with respect to gravid women health. Each therapeutic or preventive choice deserves to be weighed upon attentively. On many aspects evidence is scarce or controversial. This review will highlight the latest insights into the paramount steps in managing HBV in pregnancy, with particular attention to recommendations from recent guidelines and data from up-do-date research syntheses.

Maternal pre-pregnancy infection with hepatitis B virus and the risk of preterm birth: a population-based cohort study

BACKGROUND

Preterm birth is the leading cause of child death in children younger than 5 years. Large cohort studies in developed countries have shown that maternal hepatitis B virus infection is associated with preterm birth, but there is little reliable evidence from China and other developing countries, where hepatitis B virus prevalence is intermediate or high. Hence, we designed this study to investigate the association between pre-pregnancy hepatitis B virus infection and risk of preterm and early preterm birth.

METHODS

Between Jan 1, 2010, and Dec 31, 2012, we did a population-based cohort study using data from 489 965 rural women aged 21-49 years who had singleton livebirths from 220 counties of China who participated in the National Free Preconception Health Examination Project. Participants were divided into three groups according to their pre-pregnancy status of hepatitis B virus infection: women uninfected with hepatitis B virus (control group), women who were HBsAg positive and HBeAg negative (exposure group 1), and women who were both HBsAg and HBeAg positive (exposure group 2). The primary outcome was preterm birth (gestation at less than 37 weeks). We used log-binomial regression to estimate adjusted risk ratios (aRR) of preterm birth for women with pre-pregnancy hepatitis B virus infection, and risk of early preterm birth (gestation less than 34 weeks).

FINDINGS

489 965 women met inclusion criteria and were included in this study; of these, 20 827 (4·3%) were infected with hepatitis B virus. Compared with women who were not infected with hepatitis B virus, women who were HBsAg positive and HBeAg negative had a 26% higher risk of preterm birth (aRR 1·26, 95% CI 1·18-1·34) and women who were both HBsAg and HBeAg positive had a 20% higher risk of preterm birth (aRR 1·20, 1·08-1·32). Compared with women who were not infected with hepatitis B virus, women who were HBsAg positive and HBeAg negative manifested an 18% higher risk of early preterm birth (gestation less than 34 weeks; aRR 1·18, 1·04-1·34) and women who were both HBsAg and HBeAg positive had a 34% higher risk of early preterm birth (aRR 1·34, 1·10-1·61). Maternal pre-pregnancy hepatitis B virus infection was independently associated with higher risk of preterm birth and early preterm birth. These associations were similar in subgroups of participants as defined by baseline characteristics.

INTERPRETATION

Besides mother-to-child transmission, the risk of preterm birth in women infected with hepatitis B virus should not be neglected. Comprehensive programmes that focus on early detection of hepatitis B virus infection before pregnancy and provide appropriate medical intervention for women infected with hepatitis B virus before and during pregnancy would be helpful in improving maternal and neonatal outcomes and reducing child mortality.

FUNDING

Chinese Association of Maternal and Child Health Studies.