Reports suggest that the severity of coronavirus infection may be significantly more pronounced in men than in women.1 Studies have demonstrated that estrogen reduces both influenza virus replication in human female nasal epithelial cells2 and moderates the cytokine storm in murine models of this infection, a life-saving effect that is eliminated by oophorectomy and restored when estrogen is administered to female mice who underwent gonadectomy.3
A recent report from Wuhan, China,4 found that 109 of 118 pregnant women (92%) who tested positive for COVID-19 had mild symptoms. In addition, all women, even the 8% with severe or critical disease, had been discharged by the time of the report’s publication. There were no deaths.
Since nearly 9 of 10 nurses and nursing assistants, most respiratory therapists, a majority of pharmacists, and an overwhelming majority of pharmacy aides and technicians are women, and more than two-thirds of U.S. workers at grocery stores and fast-food counters are women,5 the findings suggesting estrogen confers relative resistance to COVID-19 infection is, at least for now, reassuring.
Clearly, this suggested benefit of estrogen protection against COVID-19 requires continued evaluation. However, it appears to add to the already confirmed benefits of this hormone in reducing the risks for heart disease, Alzheimer’s disease, and osteoporotic hip fractures.
—Avrum Z. Bluming, MD, MACP
Emeritus Clinical Professor of Medicine
University of Southern California, Los Angeles
DISCLOSURE: Dr. Bluming has been employed by RadNet and holds stock or other ownership interests in Intuitive Surgical.
1. Karlberg J, Chong DS, Lai WY: Do men have a higher case fatality rate of severe acute respiratory syndrome than women do? Am J Epidemiol 159:229-231, 2004.
2. Peretz J, Pekosz A, Lane AP, et al: Estrogenic compounds reduce influenza A virus replication in primary human nasal epithelial cells derived from female, but not male, donors. Am J Physiol Lung Cell Mol Physiol 310:L415-L425, 2016.
3. Channappanavar R, Fett C, Mack M, et al: Sex-based differences in susceptibility to severe acute respiratory syndrome (SARS) coronavirus infection. J Immunol 198:4046-4053, 2017.
4. Chen L, Li Q, Zheng D, et al: Clinical characteristics of pregnant women with COVID-19 in Wuhan, China. N Engl J Med. April 17, 2020 (early release online).
5. Robertson C, Gebeloff R: How millions of women became the most essential workers in America. The New York Times, April 18, 2020.