PRL and COVID-19: Prolactin level among those recovered from COVID-19 was more than that among non-COVID-19 groups with overall MD (95% CI) of 3.21 (1.71, 4.72) with presence of low heterogeneity (p = 0.21, I2 = 34.39%) from 3 studies [10, 12, 17] (Fig. 3).