Final answer:
The 'milk let-down reflex' is a neuroendocrine reflex initiated by a baby's sucking, leading to the release of oxytocin from the posterior pituitary and the consequent milk flow from the mammary glands.
Step-by-step explanation:
The flow of milk, which is controlled by a neuroendocrine reflex stimulated by the infant's sucking, is also called the "milk let-down reflex". During breastfeeding, the baby's sucking initiates a sequence of events: sensory nerve fibers in the areola are stimulated, triggering a neuroendocrine reflex. This causes the posterior pituitary to release the hormone oxytocin, leading to the contraction of myoepithelial cells around the alveoli in the mammary glands. This contraction pushes milk into the lactiferous ducts, ready to be discharged through the nipple pores to the feeding infant. This process is a positive feedback loop and is crucial for the continuation of milk supply during lactation.