Observational studyEuropean journal of obstetrics, gynecology, and reproductive biology2021
Association of ABO and Rh blood groups with obstetric outcomes in SARS-CoV-2 infected pregnancies: A prospective study with a multivariate analysis.
Observational study in European journal of obstetrics, gynecology, and reproductive biology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.
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Who cites it
6 citing papers in PubMed, 1 synthesis or guideline pooled it, 9 citations in OpenAlex.
- Neonatal outcomes among pregnant women with COVID-19: a systematic scoping review and meta-analysis.BMC pregnancy and childbirth · 2025Pooled it
- Blood Group Antigen Combinations and COVID-19: Complexity, Associations and Possible Clinical Relevance.Life (Basel, Switzerland) · 2026Article
- Risk Factors for Severe-Critical COVID-19 in Pregnant Women.Journal of clinical medicine · 2023Article
- Coronavirus Disease-2019 in Pregnancy.Clinics in chest medicine · 2023Review
- Blood Type Associated with the Risk of COVID-19 Infection in Pregnant Women.Diagnostics (Basel, Switzerland) · 2023Article
- ABO Blood Group in Relation to COVID-19 Susceptibility and Clinical Outcomes: A Retrospective Observational Study in the United Arab Emirates.Life (Basel, Switzerland) · 2022Article
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Authors and funding
12 authors at 10 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveTo evaluate the influence of ABO and Rh blood groups on morbidity among SARS-CoV-2 infected pregnancies.
designProspective observational study.
setting78 centers of the Spanish Obstetric Emergency Group. POPULATION: Pregnant women with SARS-CoV-2 tested with polymerase-chain-reaction between 26-February and 5-November 2020. A cohort of 1278 SARS-CoV-2(+) pregnant women was analyzed and a concurrent comparison group of 1453 SARS-COV-2(-) patients was established.
methodsData were collected from medical charts. SARS-COV-2(+) was compared with SARS-COV-2(-) for differences in distribution of blood groups. We performed multivariate analysis, controlling for maternal age and ethnicity, to evaluate association of ABO and Rh blood groups with maternal and perinatal outcomes in SARS-CoV-2(+) patients with adjusted odds ratios (aOR) and 95% confidence intervals (CI). MAIN OUTCOMES MEASURES: Medical morbidity: Symptomatic COVID-19 and medical complications. Obstetric outcomes: caesarean delivery, preterm deliveries, preterm premature rupture of membranes (PPROM), hemorrhagic events, pre-eclampsia, maternal and neonatal mortality, stillbirth.
resultsDifferences were noted between blood types and Rh for age and ethnicity comparing SARS-CoV-2(+) and SARS-CoV-2(-) groups (p < 0.05). Among the SARS-CoV-2(+) cohort, the odds of symptomatic COVID-19 and obstetric hemorrhagic event were higher in Rh+ vs Rh- mothers (aOR 1.48, 95% CI 1.02-2.14, p = 0.037, and aOR 8.72, 95% CI 1.20-63.57, p = 0.033, respectively), and PPROM were higher among blood type A vs non-A mothers (aOR 2.06, 95% CI 1.01-4.18, p = 0.046).
conclusionsIn SARS-CoV-2(+) pregnant women, Rh- status was associated with a lower risk of symptomatic COVID-19, while Rh+ and blood group A were associated with obstetric hemorrhage and PPROM, respectively.
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