975 ABO blood group, rhesus type and risk of COVID-19 in pregnant women

Abstract

OBJECTIVE: There is controversy regarding the association of ABO blood group, Rhesus (Rh) type and risk of COVID-19. We tested the hypothesis that ABO blood group and Rh type are associated with COVID-19 diagnosis and symptoms during pregnancy. STUDY DESIGN: Retrospective analysis of prospectively collected data from two labor and delivery units with universal SARS-CoV-2 testing policy between March 1 and May 31, 2020. All pregnant women tested during the study period were eligible. The primary outcome was COVID-19 diagnosis. Secondary outcomes were measures of COVID-19 severity, including symptoms, ICU admission, respiratory support and treatment for COVID-19. Outcomes were compared across ABO blood groups. Women with blood group O or Rh positive blood type were compared with non-O groups and Rh negative, respectively, using univariable and multivariable analyses. RESULTS: Of 586 pregnant women tested, 66 (11.3%) were positive. The most common ABO blood group in the cohort was O (52.2%) and 87.4% were Rh positive. Rates of the primary outcome, COVID-19 diagnosis, were not significantly different across ABO blood groups (P¼0.47). There were also no significant differences in measures of COVID-19 severity among blood groups (Table). Compared to other blood groups, the risk of COVID-19 diagnosis was not significantly different in women with group O (13.1% vs 9.3%, adjusted OR 1.43; 95% CI 0.84, 2.4). Rh positive women were at a significantly higher risk of COVID-19 diagnosis (12.3% vs 4.1%, adjusted OR 3.38; 95% CI 1.03, 11.07) and a non-significant increased risk of symptoms (6.8% vs 2.7%, adjusted OR 2.67; 95% CI 0.63, 11.32), after adjusting for ABO blood group (Figure). CONCLUSION: We found no association between ABO blood group and diagnosis or severity of COVID-19 in pregnant women. However, Rhesus positive women may be at a higher risk of COVID-19.

The Role of ABO Blood Type in Patients with SARS-CoV-2 Infection: A Systematic Review

“…Of 314 potentially relevant reports identified after eliminating duplicates, supplemented with one paper of the authors accepted for publication, 23 of them met the inclusion criteria. Five of the 23 included studies were CCS [ 18 , 22 , 23 , 24 , 25 ], and the remaining 18 were CS or cross-sectional studies [ 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ] as reported by the authors of the papers or deduced from the authors of this review.…”

“…Six studies were published in 2020 [ 22 , 27 , 28 , 34 , 35 , 39 ] and 17 studies in 2021 [ 18 , 23 , 24 , 25 , 26 , 29 , 30 , 31 , 32 , 33 , 36 , 37 , 38 , 40 , 41 , 42 , 43 ]. All included studies were carried out in the pre-vaccinal period: between February and July 2020 for studies published in 2020, and until November 2020 for those published in 2021.…”

“…All included studies were carried out in the pre-vaccinal period: between February and July 2020 for studies published in 2020, and until November 2020 for those published in 2021. Eleven of the 23 studies were carried out in Europe [ 18 , 24 , 26 , 27 , 28 , 29 , 34 , 36 , 40 , 42 , 43 ], of which five were in the United Kingdom [ 24 , 26 , 34 , 36 , 43 ], nine studies in America [ 23 , 25 , 30 , 31 , 32 , 35 , 37 , 39 , 41 ], of which seven were in the USA [ 23 , 25 , 30 , 31 , 32 , 35 , 39 ], and only three in Asia (Saudi Arabia, Iraq and Iran) [ 22 , 33 , 38 ].…”

“…Instead, other studies found no significant evidence of the correlation between blood group and occurrence of SARS-CoV-2 infection [ 18 , 23 , 32 , 36 , 37 ], while others have demonstrated only a decreased risk for contracting SARS-CoV-2 infection in individuals with blood group O [ 27 ] or an increased risk for subjects with blood group A compared with the other blood groups [ 33 , 38 ].…”

“… Forest plot for the occurrence of SARS-CoV-2 infection in patients with Blood Group AB versus non-AB [ 18 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 ]. …”