COVID-19 infection rarely activated a sickle cell crisis or caused fetal complications in pregnant women with sickle cell disease (SCD), according to results of a new study published in the Journal of Gynecology Obstetrics and Human Reproduction.

Pregnant women demonstrate increased susceptibility and more severe reactions to viral infections due to altered immune system function and physiological changes that occur during pregnancy. Lack of published information spurred Kolanska and colleagues to analyze the effects of COVID-19 infection on pregnant women with SCD.

They focused on the primary endpoint of COVID-19 infection severity, while secondary endpoints included pregnancy complications and fetal outcomes. During this time, 8 of 82 pregnant women with SCD contracted COVID-19. All 8 women were unvaccinated for COVID-19.

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Six of these women exhibited mild symptoms of the virus, independent of SCD genotype. Of the 2 remaining women, 1 was asymptomatic, while the other required admission to the intensive care unit for oxygen therapy and an emergency cesarean section due to a vaso-occlusive crisis, acute chest syndrome, and incidental preeclampsia. Following complete remission of COVID-19, another woman required induced labor due to a vaso-occlusive crisis.

Previous medical history included vaso-occlusive crises for 7 of the 8 women with 4 women experiencing this during previous pregnancies. The woman with the most severe complications had already been hospitalized twice during her current pregnancy for vaso-occlusive crises prior to her COVID-19 infection.

COVID-19 infection failed to negatively influence fetal outcomes with the infants demonstrating normal umbilical arterial blood pH and average Apgar scores of 10 at birth. Two infants exhibited low birth weight due to previously diagnosed intrauterine growth restrictions unrelated to COVID-19 infection.

“The hypothesis that a chronic inflammatory background and the hemolytic and anemic state in SCD patients might have a protective impact on COVID-19 progression has already been reported,” the authors said. However, they also speculated that “exchange transfusion could have also played a protective role, as it was performed in 38% of women.” They also stressed anti-COVID vaccination as crucial protection for pregnant women with SCD.

Overall, COVID-19 infection severity, pregnancy complications, and fetal outcomes in pregnant women with SCD did not differ significantly from the general population.


Kolanska K, Vasileva R, Lionnet F, et al. Sickle cell disease and COVID-19 in pregnant women. J Gynecol Obstet Hum Reprod. 2022;51(3):102328. doi:10.1016/j.jogoh.2022.102328