High dose inhaled nitric oxide gas (iNO) is a safe and effective respiratory therapy for pregnant women hospitalized with severe COVID-19 pneumonia, resulting in a more rapid weaning from supplemental oxygen and reduced length of hospital stay, according to a research team led by Massachusetts General Hospital (MGH). In a study published in Obstetrics & Gynecology, researchers from four Boston hospitals reported that the addition of twice-daily nitric oxide to standard of care oxygen therapy decreased the respiratory rate of pregnant women with low oxygenation levels of the blood without causing any side effects.