Do women who contract COVID-19 when pregnant have an increased risk of miscarriage?

Last updated: February 24, 2022
There is no consensus in the literature on this question. We encourage you to read the study summaries below or the studies themselves if you have access.
This short answer was generated by aggregating the answers that each of the studies below gave to the question (as indicated by State of K members) and adjusting for source quality and other factors. If key studies are missing or the answers attributed to individual studies are incorrect, the above answer could be wrong. For medical questions, don't rely on the information here. Consult a medical professional.
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YES ANSWERS
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NO ANSWERS
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NO DATA ON ANSWER


Chart summary of 7 studies examining this question

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Literature Reviews
Although we recommend you consider all of the studies below, we believe the following studies are literature reviews, which survey and evaluate many studies on this question:

SUMMARIES OF STUDIES
Total studies in list: 7
Sorted by publication year
1
Fetal Complications in COVID-19 Infected Pregnant Woman: A Systematic Review and Meta-Analysis
"Background  Pregnancy is an immunocompromised state and, for this reason, a pregnant woman is at a higher risk of getting infected as compared with a healthy individual. There is limited data available regarding the impact of COVD-19 on pregnancy; however, the case of miscarriage due to placental infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in second trimester has already been reported.Methods  We searched for all published articles in PubMed, Science Direct, Cochrane, Scopus, and Embase. The literature search produced 167 relevant publications; 67 manuscripts were further excluded because they did not satisfy our inclusion criteria. Out of the remaining 100 articles, 78 were excluded after full text screening. Therefore, a total of 22 articles were eligible for review in our study.Results  Overall, these 22 studies included a total of 7,034 participants: 2,689 (38.23%) SARS-CoV-2 positive pregnant women, of which 2,578 (95.87%) were laboratory confirmed and 111 (4.13%) were clinically diagnosed. Among the positive patients, there were 174 (6.47%) cases of abortion, of them 168 (96.55%) were spontaneous abortions and 6 (3.45%) were missed. Most patients either reported mild symptoms of fever, cough, fatigue, and anosmia or they presented asymptomatic.Conclusion  Additional investigation and rigorous research are warranted to confirm placental pathology mechanisms concerning COVID-19 to protect maternal and fetal health."
AUTHORS
Ripon Ahammed
Diana Fiorela Sánchez Velazco
Olsi Agolli
Arjola Agolli
PUBLISHED
2021 Avicenna Journal of Medicine
Literature Review
Couldn't Identify
Couldn't Identify
2
COVID-19 and cause of pregnancy loss during the pandemic: A systematic review
"Introduction: The association between Coronavirus Disease 2019 (COVID-19) and abortion has been debated since the beginning of the COVID-19 pandemic. We aimed to conduct this systematic review to understand better the potential effects of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) on fetal loss in infected mothers presented with abortion following this infection.Methods: We included articles published in PubMed/Medline, Web of Science, clinicaltrials.gov, and Embase databases in 2019 and 2020 through a comprehensive search via appropriate keywords, including COVID-19 and abortion synonyms. All studies with the abortion data in COVID-19 confirmed pregnant females were collected.Results: Out of 208 potentially relevant articles, 11 articles were eligible to include in the systematic review. The included reports were published because of the following reasons: (1) First-trimester miscarriage; (2) Late miscarriage; (3) complication of COVID-19 infection in pregnancy; (4) COVID-19 disease in artificial pregnancy. First-trimester abortion was found in 5 studies, and second-trimester abortion in 7 studies. Two patients acquired infection during the hospital stay while they were referred for abortion. Reports related to abortion in pregnant females with COVID-19 show that most miscarriages due to COVID-19 in the first trimester were due to placental insufficiency.Conclusions: There is an increased risk of abortion in mothers with a positive test result of SARS-CoV-2, which several case reports and case series have identified during the pandemic. Placental inflammation during the viral infection may result in fetal growth retardation and induce abortion. There has not been any consistent evidence of vertical transmission of the virus from mother to fetus, which requires further investigation."
AUTHORS
Mohammad Javad Nasiri
Mehdi Mirsaeidi
Farima Khalili
Sara Haddadi
Seyyedeh Neda Kazemi 1, Bahareh Hajikhani 2, Hamidreza Didar 3, Sareh Sadat Hosseini
PUBLISHED
2021 PLoS One
Literature Review
High Quality Source
Yes
Yes
3
COVID-19 and miscarriage: From immunopathological mechanisms to actual clinical evidence
"The association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the first half of pregnancy and pregnancy loss is still unknown. Infections by other coronaviruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV), appear to increase the risk of miscarriage. The purpose of this study is to assess whether SARS-CoV-2 infection increases the risk of miscarriage. Firstly, a narrative review of the literature on animal and human studies was performed to analyze the immunopathological mechanisms of SARS-CoV-2 infection during preconception and early pregnancy, by which it may increase the risk of miscarriage. Secondly, a systematic review/meta-analysis of studies was conducted to assess the prevalence of miscarriage in COVID-19 patients diagnosed during pregnancy. Meta-analysis of proportions was used to combine data, and pooled proportions were reported. Seventeen case series and observational studies and 10 prevalence meta-analyses were selected for the review. The estimate of the overall miscarriage rate in pregnant women with COVID-19 was 15.3 % (95 % CI 10.94-20.59) and 23.1 (95 % CI 13.17-34.95) using fixed and random effect models, respectively. Based on the data in the current literature, the miscarriage rate (<22 weeks gestation) in women with SARS-CoV-2 infection is in the range of normal population. Well-designed studies are urgently needed to determine whether SARS-CoV-2 infection increases the risk of miscarriage during periconception and early pregnancy."
AUTHORS
Joanne Kwak-Kim
Ricardo Barini
Manoel Sarno
Ana Nery Melo Cavalcante
Candice Torres de Melo Bezerra Cavalcante
Marcelo Borges Cavalcante
PUBLISHED
2021 PLoS One
Literature Review
High Quality Source
No
No
4
Effect of coronavirus disease 2019 (COVID-19) on maternal, perinatal and neonatal outcome: systematic review
"Objective: To evaluate the effect of coronavirus disease 2019 (COVID-19) on maternal, perinatal and neonatal outcome by performing a systematic review of available published literature on pregnancies affected by COVID-19.Methods: We performed a systematic review to evaluate the effect of COVID-19 on pregnancy, perinatal and neonatal outcome. We conducted a comprehensive literature search using PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure Database and Wan Fang Data up to and including 20 April 2020 (studies were identified through PubMed alert after that date). For the search strategy, combinations of the following keywords and medical subject heading (MeSH) terms were used: 'SARS-CoV-2', 'COVID-19', 'coronavirus disease 2019', 'pregnancy', 'gestation', 'maternal', 'mother', 'vertical transmission', 'maternal-fetal transmission', 'intrauterine transmission', 'neonate', 'infant' and 'delivery'. Eligibility criteria included laboratory-confirmed and/or clinically diagnosed COVID-19, patient being pregnant on admission and availability of clinical characteristics, including at least one maternal, perinatal or neonatal outcome. Exclusion criteria were non-peer-reviewed or unpublished reports, unspecified date and location of the study, suspicion of duplicate reporting and unreported maternal or perinatal outcomes. No language restrictions were applied.Results: We identified a high number of relevant case reports and case series, but only 24 studies, including a total of 324 pregnant women with COVID-19, met the eligibility criteria and were included in the systematic review. These comprised nine case series (eight consecutive) and 15 case reports. A total of 20 pregnant patients with laboratory-confirmed COVID-19 were included in the case reports. In the combined data from the eight consecutive case series, including 211 (71.5%) cases of laboratory-confirmed and 84 (28.5%) of clinically diagnosed COVID-19, the maternal age ranged from 20 to 44 years and the gestational age on admission ranged from 5 to 41 weeks. The most common symptoms at presentation were fever, cough, dyspnea/shortness of breath, fatigue and myalgia. The rate of severe pneumonia reported amongst the case series ranged from 0% to 14%, with the majority of the cases requiring admission to the intensive care unit. Almost all cases from the case series had positive computed tomography chest findings. All six and 22 cases that had nucleic-acid testing in vaginal mucus and breast milk samples, respectively, were negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Only four cases of spontaneous miscarriage or termination were reported. In the consecutive case series, 219/295 women had delivered at the time of reporting and 78% of them had Cesarean section. The gestational age at delivery ranged from 28 to 41 weeks. Apgar scores at both 1 and 5 min ranged from 7 to 10. Only eight neonates had birth weight < 2500 g and nearly one-t"
AUTHORS
H Yang
Y Zhang
Z Rong
M M Gil
J Juan
et al
PUBLISHED
2020 Ultrasound in Obstetrics & Gynecology
Literature Review
High Quality Source
Couldn't Identify
Couldn't Identify
5
Maternal Coronavirus Infections and Neonates Born to Mothers with SARS-CoV-2: A Systematic Review
"The coronavirus disease 2019 (COVID-19) pandemic is continuously affecting the lives of all people. Understanding the impact of COVID-19 on pregnancy in terms of morbidity, mortality, and perinatal maternal and fetal outcomes is essential to propose strategies for prevention and infection control. Here, we conducted a systematic review to investigate pregnant women infected with COVID-19 in terms of signs and symptoms, type of delivery, comorbidities, maternal and neonatal outcomes, and the possibility of vertical transmission. A search on Embase and PubMed databases was performed on 31 October 2020. Observational studies and case reports on pregnant women infected with COVID-19 were included without language restrictions. The 70 selected studies included a total of 1457 pregnant women diagnosed with COVID-19 in the first, second, and third trimesters of pregnancy. The most common signs and symptoms were fever, cough, and nausea. The most frequent comorbidities were obesity, hypertensive disorders, and gestational diabetes. Among maternal and fetal outcomes, premature birth (n = 64), maternal death (n = 15), intrauterine fetal death or neonatal death (n = 16), cases of intrauterine fetal distress (n = 28), miscarriage (n = 7), decreased fetal movements (n = 19), and severe neonatal asphyxia (n = 5) were the most frequent. Thirty-nine newborns tested positive for SARS-CoV-2. Additionally, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was detected in the placenta (n = 13) and breast milk (n = 6). This review indicates that COVID-19 during pregnancy can result in maternal, fetal, and neonatal complications. In addition, SARS-CoV-2 viral exposure of neonates during pregnancy and delivery cannot be ruled out. Thus, we highlight the need for long-term follow-up of newborns from mothers diagnosed with COVID-19 to establish the full implications of SARS-CoV-2 infection in these children."
AUTHORS
Carolina Rodrigues Mendonça
Jalsi Tacon Arruda
Matias Noll
Ana Paula Dos Santos Rodrigues
Carolina Leão de Moraes
Waldemar Naves do Amaral
PUBLISHED
2020 Healthcare
Literature Review
Couldn't Identify
Couldn't Identify
6
The effect of coronavirus infection (SARS-CoV-2, MERS-CoV, and SARS-CoV) during pregnancy and the possibility of vertical maternal–fetal transmission: a systematic review and meta-analysis
"In general, based on the published data collected, fever, cough, and myalgia were the most common clinical features, while the predominant abnormal laboratory findings reported were lymphocytopenia and C-reactive protein. Bilateral pneumonia and ground-glass opacity were the most common radiological abnormal findings. Oxygen therapy was the most common treatment option used while bacterial coinfection was treated by antibiotics therapy, and viral pathogen was treated by antiviral therapy. Among the coronavirus species, MERS-CoV was the leading cause of severe cases in infected pregnant women. Pregnant women infected with coronaviruses are at increased risk of adverse obstetrical outcomes, compared with the general population. The infection outcome was mainly associated with a relatively higher rate of cesarean delivery, preterm birth, intensive care unit admission, preeclampsia, miscarriage, fetal distress, and perinatal death. None of the studies reported transmission of CoV from the mother to the fetus in utero. This may be due to a very low expression of angiotensin-converting enzyme 2 (ACE2) in early maternal–fetal interface cells as suggested by different experts."
AUTHORS
Eyob Getu
Ephrem Awulachew
Kuma Diriba
PUBLISHED
2020 European Journal of Medical Research
Literature Review
Yes
Yes
7
Outcome of coronavirus spectrum infections (SARS, MERS, COVID-19) during pregnancy: a systematic review and meta-analysis
"ObjectiveThe aim of this systematic review was to report pregnancy and perinatal outcomes of coronavirus spectrum infections, and particularly coronavirus 2019 (COVID-19) disease because of severe acute respiratory syndrome–coronavirus-2 infection during pregnancy.Data SourcesMedline, Embase, Cinahl, and Clinicaltrials.gov databases were searched electronically utilizing combinations of word variants for coronavirus or severe acute respiratory syndrome or SARS or Middle East respiratory syndrome or MERS or COVID-19 and pregnancy. The search and selection criteria were restricted to English language.Study Eligibility CriteriaInclusion criteria were hospitalized pregnant women with a confirmed coronavirus related–illness, defined as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), or COVID-19.Study Appraisal and Synthesis MethodsWe used meta-analyses of proportions to combine data and reported pooled proportions, so that a pooled proportion may not coincide with the actual raw proportion in the results. The pregnancy outcomes observed included miscarriage, preterm birth, preeclampsia, preterm prelabor rupture of membranes, fetal growth restriction, and mode of delivery. The perinatal outcomes observed were fetal distress, Apgar score <7 at 5 minutes, neonatal asphyxia, admission to a neonatal intensive care unit, perinatal death, and evidence of vertical transmission.ResultsNineteen studies including 79 hospitalized women were eligible for this systematic review: 41 pregnancies (51.9%) affected by COVID-19, 12 (15.2%) by MERS, and 26 (32.9%) by SARS. An overt diagnosis of pneumonia was made in 91.8%, and the most common symptoms were fever (82.6%), cough (57.1%), and dyspnea (27.0%). For all coronavirus infections, the pooled proportion of miscarriage was 64.7% (8/12; 95% confidence interval, 37.9-87.3), although reported only for women affected by SARS in two studies with no control group; the pooled proportion of preterm birth <37 weeks was 24.3% (14/56; 95% confidence interval, 12.5–38.6); premature prelabor rupture of membranes occurred in 20.7% (6/34; 95% confidence interval, 9.5–34.9), preeclampsia in 16.2% (2/19; 95% confidence interval, 4.2–34.1), and fetal growth restriction in 11.7% (2/29; 95% confidence interval, 3.2–24.4), although reported only for women affected by SARS; 84% (50/58) were delivered by cesarean; the pooled proportion of perinatal death was 11.1% (5/60; 95% confidence interval, 84.8–19.6), and 57.2% of newborns (3/12; 95% confidence interval, 3.6–99.8) were admitted to the neonatal intensive care unit. When focusing on COVID-19, the most common adverse pregnancy outcome was preterm birth <37 weeks, occurring in 41.1% of cases (14/32; 95% confidence interval, 25.6–57.6), while the pooled proportion of perinatal death was 7.0% (2/41; 95% confidence interval, 1.4–16.3). None of the 41 newborns assessed showed clinical signs of vertical transmission.ConclusionIn hospitalized"
AUTHORS

Gabriele Saccone
Asma Khalil
Daniele Di Mascio
PUBLISHED
2020 American Journal of Obstetrics & Gynecology
Literature Review
Couldn't Identify
Couldn't Identify