Doctors are wondering if giving men two female sex hormones could make them more likely to survive the novel coronavirus.
Across the globe, women from most countries have been less likely to become abruptly ill with the virus, and less likely to die from it.
This has led many researchers to wonder if the hormones mainly produced in women could be protective, reported The New York Times.
Two hospitals in the US are now putting that theory to the test, giving men estrogen or progesterone for a limited amount of time to see if it boosts their immune systems, decreases inflammation and reduces the severity of the illness.
The differences in death rates among men and women have been apparent from early on in the pandemic.
Last month, Italy’s public health research agency said that more than 70 percent of the country’s deaths have been in men.
And, in February, China’s Center for Disease Control and Prevention said the fatality rate among men with coronavirus was 65 percent higher than among women.
Scientists say they don’t know why women seem less likely to die, but have suggested that women naturally tend to have stronger immune systems and are less likely to have long-term health conditions which make patients more vulnerable.
In China, researchers pointed the finger at men being more likely to smoke and drink, but this was a cultural factor which may be different in other countries.
This soon became apparent in the US. In New York, more than 60 percent of the state’s deaths have been among men.
Early research has suggested the hormones may reduce the number of ACE2 receptors on the surfaces of cells that the virus uses to enter the body.