lactational

Lactational is an adjective relating to lactation, the physiological process by which milk is produced and secreted by the mammary glands to feed offspring. In humans and other mammals, lactation begins during late pregnancy and continues after birth, with milk synthesis and ejection governed by hormonal signals and mechanical stimulation.

In humans, the key hormones are prolactin, which stimulates milk production in the milk-producing cells, and oxytocin, which triggers the let-down reflex to eject milk from the nipple. Milk production rises after birth as the infant nurses. Lactation is commonly described in stages: lactogenesis I (the early formation of secretory tissue during pregnancy), lactogenesis II (the onset of copious milk secretion in the first days after birth), and lactogenesis III (maintenance of mature milk supply with ongoing breastfeeding).

Lactation underpins breastfeeding, providing nutrition and immunological benefits for infants. It also underlies birth-spacing practices such as the lactational amenorrhea method, which can reduce the risk of pregnancy when breastfeeding is frequent and exclusive.

Medical issues related to lactation can affect milk supply or comfort. These include lactational mastitis, clogged ducts, and sore nipples, which may require medical or lactation-support interventions. Milk production and composition vary across mammalian species, reflecting adaptations to different offspring and ecological contexts.