The mean 5-HT concentrations in breast milk in primiparous mothers immediately before nursing, 1 to 2 h after nursing, and immediately before the next nursing event were 23.6 ± 1.48, 22.82 ± 1.65, and 21.84 ± 1.31 ng/mL, respectively; mean 5-HT concentrations in multiparous women were 25.4 ± 1.65, 23.6 ± 2.20, or 22.4 ± 2.09 ng/mL, respe…[Read more]