Prevention and Management of Viral Hepatitis in Pregnancy

Pregnancy and fetal outcomes of chronic hepatitis C mothers with viremia in China

BACKGROUND

Data that assess maternal and infant outcomes in hepatitis C virus (HCV)-infected mothers are limited.

AIM

To investigate the frequency of complications and the associated risk factors.

METHODS

We performed a cohort study to compare pregnancy and fetal outcomes of HCV-viremic mothers with those of healthy mothers. Risk factors were analyzed with logistic regression.

RESULTS

Among 112 consecutive HCV antibody-positive mothers screened, we enrolled 79 viremic mothers. We randomly selected 115 healthy mothers from the birth registry as the control. Compared to healthy mothers, HCV mothers had a significantly higher frequency of anemia [2.6% (3/115) vs 19.0% (15/79), P < 0.001] during pregnancy, medical conditions that required caesarian section [27.8% (32/115) vs 48.1% (38/79), P = 0.004], and nuchal cords [9.6% (11/115) vs 34.2% (27/79), P < 0.001]. In addition, the mean neonatal weight in the HCV group was significantly lower (3278.3 ± 462.0 vs 3105.1 ± 459.4 gms; P = 0.006), and the mean head circumference was smaller (33.3 ± 0.6 vs 33.1 ± 0.7 cm; P = 0.03). In a multivariate model, HCV-infected mothers were more likely to suffer anemia [adjusted odds ratio (OR): 18.1, 95% confidence interval (CI): 4.3-76.6], require caesarian sections (adjusted OR: 2.6, 95%CI: 1.4-4.9), and have nuchal cords (adjusted OR: 5.6, 95%CI: 2.4-13.0). Their neonates were also more likely to have smaller head circumferences (adjusted OR: 2.1, 95%CI: 1.1-4.3) and lower birth weights than the average (≤ 3250 gms) with an adjusted OR of 2.2 (95%CI: 1.2-4.0). The vertical transmission rate was 1% in HCV-infected mothers.

CONCLUSION

Maternal HCV infections may associate with pregnancy and obstetric complications. We demonstrated a previously unreported association between maternal HCV viremia and a smaller neonatal head circumference, suggesting fetal growth restriction.

Universal Hepatitis B Antibody Screening and Vaccination in Pregnancy: A Cost-Effectiveness Analysis

OBJECTIVE

To evaluate the cost effectiveness of universal screening for hepatitis B immunity and vaccination among pregnant women in the United States.

METHODS

We designed a decision-analytic model to evaluate the outcomes, costs, and cost effectiveness associated with universal hepatitis B virus (HBV) immunity screening in pregnancy with vaccination of susceptible individuals compared with no screening. A theoretical cohort of 3.6 million women, the approximate number of annual live births in the United States, was used. Outcomes included cases of HBV, hepatocellular carcinoma, decompensated cirrhosis, liver transplant and death, in addition to cost and quality-adjusted life-years (QALYs). Model inputs were derived from the literature, and the willingness-to-pay threshold was $50,000 per QALY. Univariate sensitivity analyses and Monte Carlo simulation models were performed to evaluate the robustness of the results.

RESULTS

In a theoretical cohort of 3.6 million women, universal HBV immunity screening and vaccination resulted in 1,702 fewer cases of HBV, seven fewer cases of decompensated cirrhosis, four fewer liver transplants, and 11 fewer deaths over the life expectancy of a woman after pregnancy. Universal screening and vaccination were found to be cost effective, with an incremental cost-effectiveness ratio of $1,890 per QALY. Sensitivity analyses demonstrated the model was robust even when the prevalence of HBV immunity was high and the annual risk of HBV acquisition low.

CONCLUSION

Among pregnant women in the United States, universal HBV immunity screening and vaccination of susceptible persons is cost effective compared with not routinely screening and vaccinating.

Hepatitis E Virus Infection-Immune Responses to an Underestimated Global Threat

Infection with the hepatitis E virus (HEV) is one of the main ubiquitous causes for developing an acute hepatitis. Moreover, chronification plays a predominant role in immunocompromised patients such as transplant recipients with more frequent severe courses. Unfortunately, besides reduction of immunosuppression and off-label use of ribavirin or pegylated interferon alfa, there is currently no specific anti-viral treatment to prevent disease progression. So far, research on involved immune mechanisms induced by HEV is limited. It is very difficult to collect clinical samples especially from the early phase of infection since this is often asymptomatic. Nevertheless, it is certain that the outcome of HEV-infected patients correlates with the strength of the proceeding immune response. Several lymphoid cells have been identified in contributing either to disease progression or achieving sustained virologic response. In particular, a sufficient immune control by both CD4⁺ and CD8⁺ T cells is necessary to prevent chronic viral replication. Especially the mechanisms underlying fulminant courses are poorly understood. However, liver biopsies indicate the involvement of cytotoxic T cells in liver damage. In this review, we aimed to highlight different parts of the lymphoid immune response against HEV and point out questions that remain unanswered regarding this underestimated global threat.

Guideline No. 409: Intrauterine Fetal Diagnostic Testing in Women with Chronic Viral Infections

OBJECTIVE

This revised guideline provides updated information for the care of women with chronic viral infections who require intrauterine fetal diagnostic testing.

TARGET POPULATION

Women with chronic viral infections who are pregnant or planning a pregnancy.

OPTIONS

Non-invasive screening tests for diagnosis: maternal serum placental analytes with or without nuchal translucency, sonography, maternal serum cell-free placental DNA; and intrauterine fetal diagnostic testing: amniocentesis, chorionic villus sampling, cordocentesis.

OUTCOMES

The recommendations in this guideline have the potential to decrease or eliminate morbidity and mortality in women with chronic viral infections and their infants, which is associated with significant health and economic outcomes.

EVIDENCE

Published literature was retrieved through searches of PubMed, guidelines of national societies (Society of Obstetricians and Gynaecologists of Canada, American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine, other international societies), and the Cochrane Library using appropriate controlled vocabulary (amniocentesis, chorionic villus sampling, cordocentesis, procedure pregnancy loss risk, viral vertical transmission, fetal and neonatal infection) and keywords (maternal infection or exposure, hepatitis B, hepatitis C, human immunodeficiency virus). Results were restricted to systematic reviews, randomized controlled trials or controlled clinical trials (if available), and observational case-control studies or case series from 2012 to 2019 published in English or French. Studies from 1966 to 2002 were previously reviewed in the SOGC guideline No. 123: Amniocentesis and Women with Hepatitis B, Hepatitis C, or Human Immunodeficiency Virus, and those from 2002 to 2012 were previously reviewed in the SOGC guideline No. 309: Prenatal Invasive Procedures in Women With Hepatitis B, Hepatitis C, and/or Human Immunodeficiency Virus Infections. Updated literature searches were completed regularly through August 2019 and were incorporated into this guideline.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

The intended users are maternity care providers and women with chronic viral infections. This guideline provides information to educate and counsel these women, and to offer them reproductive options. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Brazilian Protocol for Sexually Transmitted Infections 2020: viral hepatitis

This article discusses viral hepatitis, a theme addressed by the Clinical Protocol and Therapeutic Guidelines to Comprehensive Care for People with Sexually Transmitted Infections and, more precisely, by the Clinical Protocols and Therapeutic Guidelines for Hepatitis B and Hepatitis C and Coinfections, published by the Brazilian Ministry of Health. Besides the broad spectrum of health impairment, hepatitis A, B, and C viruses also present different transmission forms, whether parenteral, sexual, vertical, or fecal-oral. Among the strategies suggested for the control of viral hepatitis, in addition to behavioral measures, are expanded diagnosis, early vaccination against hepatitis A and hepatitis B viruses, and access to available therapeutic resources. Considering vertical transmission of the hepatitis B and hepatitis C viruses, screening for pregnant women with chronic hepatitis B and C is an essential perinatal health strategy, indicating with precision those who can benefit from the prophylactic interventions.

Viral hepatitis A, B, and C are responsible for more than 1.34 million deaths worldwide every year, from which 66% are the result of hepatitis B, 30% of hepatitis C, and 4% of hepatitis A.

[Brazilian Protocol for Sexually Transmitted Infections 2020: viral hepatitis]

This article discusses viral hepatitis, a theme addressed by the Clinical Protocol and Therapeutic Guidelines to Comprehensive Care for People with Sexually Transmitted Infections and, more precisely, by the Clinical Protocols and Therapeutic Guidelines for Hepatitis B and Hepatitis C and Coinfections, published by the Brazilian Ministry of Health. Besides the broad spectrum of health impairment, hepatitis A, B and C viruses also present different forms of transmission, whether parenteral, sexual, vertical or oral. Among the strategies suggested for the control of viral hepatitis, in addition to behavioral measures, are expanded diagnosis, early vaccination against hepatitis A and hepatitis B viruses, and access to available therapeutic resources. Considering vertical transmission of the hepatitis B and hepatitis C viruses, screening for pregnant women with chronic hepatitis B and C is an important perinatal health strategy, indicating with precision those who can benefit from the prophylactic interventions.

Towards the Improved Accuracy of Hepatitis E Diagnosis in Vulnerable and Target Groups: A Global Perspective on the Current State of Knowledge and the Implications for Practice

The hepatitis E virus (HEV) is a positive single-stranded, icosahedral, quasi-enveloped RNA virus in the genus Orthohepevirus of the family Hepeviridae. Orthohepevirus A is the most numerous species of the genus Orthohepevirus and consists of eight different HEV genotypes that can cause infection in humans. HEV is a pathogen transmitted via the fecal-oral route, most commonly by consuming fecally contaminated water. A particular danger is the HEV-1 genotype, which poses a very high risk of vertical transmission from the mother to the fetus. Several outbreaks caused by this genotype have been reported, resulting in many premature births, abortions, and also neonatal and maternal deaths. Genotype 3 is more prevalent in Europe; however, due to the openness of the market, i.e., trade-in animals which represent a natural reservoir of HEV (such as pigs), there is a possibility of spreading HEV infections outside endemic areas. This problem is indeed global and requires increased hygiene measures in endemic areas, which entails special care for pregnant women in both endemic and non-endemic regions. As already highlighted, pregnant women could have significant health consequences due to the untimely diagnosis of HEV infection; hence, this is a population that should be targeted with a specific combination of testing approaches to ensure optimal specificity and sensitivity. Until we advance from predominantly supportive treatment in pregnancy and appraise the safety and efficacy of a HEV vaccine in this population, such screening approaches represent the mainstay of our public health endeavors.

Directive clinique no 409 : Tests diagnostiques fœtaux intra-utérins en cas d'infection virale chronique maternelle

OBJECTIF

La présente directive clinique révisée met à jour les renseignements sur la prestation de soins aux femmes atteintes d'une infection virale chronique devant se soumettre à un test diagnostique fœtal intra-utérin.

POPULATION CIBLE

Femmes atteintes d'une infection virale chronique qui sont enceintes ou prévoient le devenir.

OPTIONS

Tests de dépistage non invasifs à des fins diagnostiques : marqueurs placentaires sériques maternels avec ou sans mesure de la clarté nucale, échographie, ADN fœtal libre circulant dans le sang maternel; et tests diagnostiques fœtaux intra-utérins : amniocentèse, biopsie choriale (choriocentèse), cordocentèse.

ISSUES

Les recommandations de la présente directive clinique pourraient réduire ou éliminer la morbi-mortalité chez les femmes atteintes d'une infection virale chronique et leurs nourrissons, ce qui est associé à d'importantes conséquences sur les plans de la santé et de l'économie. DONNéES PROBANTES: La littérature publiée a été recueillie au moyen de recherches dans les bases de données PubMed et Cochrane Library ainsi que dans les directives cliniques de sociétés médicales nationales et internationales (Société des obstétriciens et gynécologues du Canada, American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine et d'autres sociétés internationales) en utilisant un vocabulaire (amniocentesis, chorionic villus sampling, cordocentesis, procedure pregnancy loss risk, viral vertical transmission, fetal and neonatal infection) et des mots clés (maternal infection or exposure, hepatitis B, hepatitis C, human immunodeficiency virus) contrôlés et appropriés. Les résultats retenus se limitent aux revues systématiques, aux essais cliniques randomisés ou aux essais cliniques comparatifs (si disponibles) et aux études cas-témoins observationnelles ou études de série de cas publiées entre 2012 et 2019 en anglais ou en français. Les études publiées entre 1966 et 2002 ont déjà été examinées dans la directive clinique de la SOGC n^o 123, L'amniocentèse chez les femmes infectées par l'hépatite B, l'hépatite C ou le virus de l'immunodéficience humaine; les études publiées entre 2002 et 2012 ont quant à elles été examinées dans la directive clinique de la SOGC n^o 309, Interventions effractives prénatales chez les femmes qui présentent des infections par le virus de l'hépatite B, le virus de l'hépatite C et/ou le virus de l'immunodéficience humaine. De nouvelles recherches ont été effectuées dans la littérature jusqu'en août 2019, puis ont été intégrées à la présente directive clinique. MéTHODES DE VALIDATION: L'auteur a évalué la qualité des données probantes et la solidité des recommandations au moyen du cadre méthodologique GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Consulter l'annexe A en ligne (le tableau A1 pour les définitions et le tableau A2 pour les interprétations des recommandations fortes et faibles). PUBLIC VISé: Les utilisateurs prévus sont des fournisseurs de soins de maternité et les femmes atteintes d'une infection virale chronique. Cette directive fournit des renseignements pour renseigner et conseiller ces femmes et leur offrir des options de procréation. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Universal Screening and Vaccination for Hepatitis B in Pregnancy: The Time Is Now

Recommendations for screening for hepatitis B immunity in pregnancy and vaccinating susceptible women vary among professional societies. The American College of Obstetricians and Gynecologists recommends vaccinating high-risk women for hepatitis B. However, only one fourth of U.S. adults have received a complete hepatitis B vaccination series. Because two thirds of individuals with chronic hepatitis B are unaware of their diagnosis, risk-based screening for immunity followed by vaccination of susceptible women may not identify and protect all women at risk. Acquisition of hepatitis B poses short-term and long-term risks to maternal and fetal health, an outcome that can be prevented by vaccination. Hepatitis B vaccination in pregnancy is safe and efficacious and can be completed during the course of prenatal care. Universal screening for hepatitis B immunity and vaccination of susceptible women in pregnancy should be a priority during prenatal care. Cost-effectiveness studies are needed to validate this approach.

Hepatitis E virus infection during pregnancy

BACKGROUND

Hepatitis E virus (HEV) generally causes self-limiting viral hepatitis. However, in pregnant women, HEV infection can be severe and has been associated with up to 30% mortality in the third trimester. Additionally, HEV infection in pregnancy is also associated with high rates of preterm labor and vertical transmission.

MAIN BODY

HEV is now recognized as a global health problem in both developing and industrialized countries. HEV can be transmitted via the fecal-oral route, zoonotic route, and blood transfusion route. An altered immune status, hormonal levels, and viral factors may be related to the severity of the disease. Currently, no established treatment is available for HEV in pregnant women. A Chinese vaccine has been demonstrated to be protective against HEV in the general population and seems to be safe in pregnancy; however, its safety and efficacy in a large population of pregnant women remain to be determined.

CONCLUSION

This review summarizes the current knowledge about HEV infection during pregnancy and focuses on the epidemiology, clinical manifestations, mechanisms underlying severe liver injury, and management and prevention of HEV infection during pregnancy. Considering that HEV infection during pregnancy may result in poor outcomes, screening for and monitoring HEV infection early in pregnancy should be taken into account. In addition, a better understanding of the pathogenesis will help to develop potential treatment strategies targeting HEV infection in pregnancy.

Hepatitis B-management of acute infection and active inflammation in pregnancy-a hepatologist's perspective

Women at childbearing age and pregnant ladies living in the areas of high or intermediate prevalence of hepatitis B virus (HBV) remain at risk of getting the infection and passing the infections to their offspring via mother-to-child transmission (MTCT) of HBV. HBV infection may affect the mothers by active hepatitis, very occasionally liver cirrhosis and rarely fulminant hepatitis and liver failure. The virus may be transmitted to the babies despite immunoprophylaxis in the setting of very high maternal viral load. Tenofovir disoproxil fumarate (TDF) has been shown to be efficacious to reduce MTCT of HBV, which contributes to the elimination of chronic HBV infection by 2030, the goal set by World Health Organization.

Hepatitis B in Pregnant Women and their Infants

Chronic hepatitis B is a global health problem affecting approximately 350 million to 400 million individuals worldwide, and mother to child transmission remains the major mode of transmission. Approximately 50% of chronically infected individuals acquire infection, either perinatally or early in childhood, predominantly in areas where hepatitis B virus (HBV) is endemic. Management of HBV in pregnancy presents a unique set of challenges. All infants born of hepatitis B surface antigen-positive mothers should receive postexposure immune prophylaxis with hepatitis B immunoglobulin and HBV vaccination within 24 hours of birth and need close follow-up for the first few years of life.

Liver Disease in Pregnancy and Transplant

PURPOSE OF REVIEW

The purpose of this review is to discuss current and new knowledge regarding liver disease in pregnancy and pregnancy post-liver transplantation.

RECENT FINDINGS

Severe liver disease associated with pregnancy is rare. Liver biopsy is rarely needed for diagnosis but is safe in selected cases. Intrahepatic cholestasis of pregnancy (ICP) with serum bile acids level > 40 μmol/L is associated with adverse fetal outcomes. Ursodeoxycholic acid should be initiated at diagnosis. Portal hypertension can worsen during pregnancy and screening endoscopy should be performed in the 2nd trimester. Maternal hepatitis B antiviral therapy can be considered in the 3rd trimester if HVB DNA > 200,000 IU/ml. Tacrolimus is the optimal immunosuppressive therapy during pregnancy post-transplantation. Preconception renal function predicts pregnancy outcome. Overall, the outcome of pregnancy post-transplantation is good but there is an increased risk of preterm delivery, low birth weight, hypertension, and pre-eclampsia. Liver disease of pregnancy can be divided into diseases unique to pregnancy, exacerbated by pregnancy or coexisting with pregnancy. Overall, the outcome of pregnancy post-liver transplantation is good.

Gastrointestinal diseases during pregnancy: what does the gastroenterologist need to know?

Pregnancy is characterized by numerous physiological changes that may lead to a diversity of symptoms and frequently to gastrointestinal complaints, such as heartburn, nausea and vomiting, or constipation. Chronic gastrointestinal diseases require treatment maintenance during this period, raising the challenging question whether outcomes beneficial to the mother may be harmful for the fetus. In addition, certain diseases, such as acute fatty liver of pregnancy, only develop during pregnancy and may require urgent procedures, such as fetus delivery. Even though they are not present in our day-to-day practice, knowledge of pregnancy-related diseases is fundamental and collaboration between gastroenterologists and obstetricians is often necessary. Herein, we review pregnancy-related diseases and systematize the most appropriate treatment choices according to the recent literature and guidelines, so that the article can serve as a guide to the gastroenterologist regarding the medical approach to pregnancy-related gastrointestinal and liver diseases and their therapeutic management.

Hepatitis C in Pregnancy

The prevalence of hepatitis C in pregnancy is as high as 3.6% in large cohorts. The prevalence of hepatitis C acquired by vertical transmission is 0.2% to 0.4% in the United States and Europe. Although screening is not recommended in the absence of certain risk factors, the importance of understanding hepatitis C in pregnancy lies in its association with adverse maternal and neonatal outcomes. There is potential for those infants infected by vertical transmission to develop chronic hepatitis C, cirrhosis or hepatocellular carcinoma. The risk of vertical transmission is increased when mothers are co-infected with Human Immunodeficiency Virus (HIV) or possess a high viral load. There is no clear data supporting that mode of delivery increases or reduces risk. Breastfeeding is not associated with increased risk of transmission. Premature rupture of membranes, invasive procedures (such as amniocentesis), intrapartum events, or fetal scalp monitoring may increase risk of transmission. In pregnant patients, hepatitis C is diagnosed with a positive ELISA-3 and detectable Hepatitis C Virus (HCV) RNA viral load. Infants born to HCV-infected mothers should be tested for either HCV RNA on at least two separate occasions. Although prevention is not possible, there may be a role for newer direct acting anti-viral medications in the future.

Hepatitis E and pregnancy: current state

Hepatitis E virus (HEV) is responsible for more than 50% of acute viral hepatitis cases in endemic countries. Approximately 2 billion individuals live in hepatitis E-endemic areas and, therefore, are at risk of infection. According to World Health Organization, HEV causes about 20.1 million infections and 70 000 deaths every year. In developing countries with poor sanitation, this disease is transmitted through contaminated water and is associated with large outbreaks, affecting hundreds or thousands of people. In developed countries, autochthonous cases of HEV have been increasingly recognized in the past several years. Hepatitis E virus typically causes an acute, self-limiting illness similar to other acute viral hepatitis, such as hepatitis A or B, with about 0.2% to 1% mortality rate in the general population. However, the course of hepatitis E in pregnancy is different than the mild self-constraining infection described in other populations. During pregnancy, HEV infection can take a fulminant course, resulting in fulminant hepatic failure, membrane rupture, spontaneous abortions, and stillbirths. Studies from various developing countries have shown a high incidence of HEV infection in pregnancy with a significant proportion of pregnant women progressing to fulminant hepatitis with a fatality rate of up to 30%. The present review will highlight new aspects of the HEV infection and pregnancy.

Management of HIV Infection during Pregnancy in the United States: Updated Evidence-Based Recommendations and Future Potential Practices

All HIV-infected women contemplating pregnancy should initiate combination antiretroviral therapy (cART), with a goal to achieve a maternal serum HIV RNA viral load beneath the laboratory level of detection prior to conceiving, as well as throughout their pregnancy. Successfully identifying HIV infection during pregnancy through screening tests is essential in order to prevent in utero and intrapartum transmission of HIV. Perinatal HIV transmission can be less than 1% when effective cART, associated with virologic suppression of HIV, is given during the ante-, intra-, and postpartum periods. Perinatal HIV guidelines, developed by organizations such as the World Health Organization, American College of Obstetricians and Gynecologists, and the US Department of Health and Human Services, are constantly evolving, and hence the aim of our review is to provide a useful concise review for medical providers caring for HIV-infected pregnant women, summarizing the latest and current recommendations in the United States.

The pregnant healthcare worker: fact and fiction

PURPOSE OF REVIEW

A pregnant healthcare worker (HCW) may be at risk of occupational exposure to pathogens associated with increased maternal morbidity and mortality as well as perinatal complications. In this article, we review recent literature on infectious diseases commonly encountered in the healthcare setting and of highest concern for a pregnant HCW, focusing on prevention and management of exposures.

RECENT FINDINGS

Pregnancy does not seem to be an independent risk factor for occupationally acquired infectious diseases. Vaccination and standard precautions continue to be the most effective means of preventing transmission to HCWs. Pandemic 2009 influenza A (H1N1) is associated with increased risk of fetal death, highlighting the importance of influenza vaccination. A recent meta-analysis highlights the safety of influenza vaccination during pregnancy. New treatments for hepatitis C have not been studied in pregnancy but pose an important area for research and advancement. Cytomegalovirus immunoglobulin may play a role in postexposure prophylaxis but recent results are inconclusive.

SUMMARY

Primary prevention with vaccination and use of appropriate infection control precautions is imperative for prevention of occupationally acquired infectious diseases. Pregnant HCWs with occupational exposure to communicable diseases should be evaluated immediately for appropriate postexposure prophylaxis and followed for development of active infection.

[Acute herpesviridae hepatitis during pregnancy: A review]

Viral hepatitis are well defined during pregnancy, including hepatitis A, B, C, D or E. In contrast, viral hepatitis called non-alphabetic, like viruses Herpesviridae family hepatitis [cytomegalovirus (CMV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV) or herpes simplex virus (HSV)] are rarely described. The aim of this article is to make a focus on the care of these viral herpesviridae hepatitis during pregnancy. Herpes hepatitis is more common during pregnancy, with a neonatal risk at peripartum period. VZV infection can cause disease to the fetus, with possible vertical transmission, and induce congenital or neonatal varicella. While EBV infection during pregnancy seems benign, the CMV is a high risk of birth defects. The management of these patients therefore depends on the gestational age, but especially the type of virus involved. The diagnosis is therefore essential to adapt treatment and obstetrical care.