Figure 1From: Early androgen exposure and human gender development Median urinary testosterone concentrations in male and female infants from 7Â days to 6Â months of age. Error bars represent the interquartile range. Testosterone was measured at day 7 postnatal (D7) and then monthly from 1Â month (M1) to 6Â months (M6) of age. Urinary testosterone was measured using HPLC-tandem mass spectrometry. Urinary testosterone concentrations are higher in boys than in girls, and testosterone peaks in boys at 1Â month of age, is lower before and after this age, and declines to baseline by about age 6Â months. The figure is reproduced from [78] by permission of Elsevier.Back to article page