Physiologic changes in serotonin concentrations in breast milk during lactation

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Vol. 79-80; p. 110969
• Main Authors: Maeda, Tomoji, Shioyama, Aki, Tairabune, Tomohiko, Takeda, Rika, Sanbe, Atsushi, Kikuchi, Akihiko, Kudo, Kenzo, Chiba, Takeshi
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Inc 01.11.2020; Elsevier Limited
• Subjects: Baby foods; Body mass index; Breast; Breast milk; Breastfeeding; Breastfeeding & lactation; Cesarean section; Colostrum; Gestational age; Homeostasis; Infants; Investigations; Laboratories; Lactation; Lipids; Mammary gland; Mammary glands; Milk; Nursing; Oils & fats; Physiologic changes; Pregnancy; Proteins; Questionnaires; Serotonin; Women; Serotonin; Lactation; Breastfeeding; Physiologic changes; Breast milk
• ISSN: 0899-9007; 1873-1244
• DOI: 10.1016/j.nut.2020.110969

Serotonin (5-hydroxytryptamine; 5-HT) plays an important role in milk volume homeostasis in the mammary glands during lactation, and 5-HT in milk also may affect infant development. The aim of this study was to investigate changes in 5-HT concentration in breast milk according to the duration of lactation and evaluate whether the 5-HT concentration varied before and after nursing. Healthy nursing Japanese women who had a natural delivery or underwent a cesarean delivery at Iwate Medical University Hospital were included in this study. The mean 5-HT concentration in milk was obtained from multiparous mothers 6 to 7 d after delivery (colostrum) and was significantly higher compared with primiparous mothers (24.3 ± 2.63 versus 18.5 ± 2.60 ng/mL). Additionally, mean 5-HT concentration increased with increasing lactation duration in primiparous women (colostrum: 18.5 ± 2.60; 1 mo postdelivery: 19.8 ± 2.46; 3 mo postdelivery: 22.7 ± 2.55 ng/mL); in particular, the mean 5-HT concentration in breast milk 3 mo after delivery was significantly higher than in colostrum. 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, respectively. There was no significant difference in 5-HT concentrations at each time point between the groups. This information may be useful in determining the role of 5-HT in breast milk on infant development and growth. •Serotonin (5-hydroxytryptamine; 5-HT) levels were significantly higher in colostrum of multi- versus primiparous mothers.•Mean 5-HT concentration increased during lactation in primiparous women.•Mean 5-HT levels were similar for multi- versus primiparous women before and after nursing.•Physiologic changes of 5-HT concentrations in milk may aid infant health studies.