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Definition

Lactation is the medical term for breastfeeding, a natural method of feeding an infant from birth to the time he or she can eat solid food. Human milk contains the ideal amount of nutrients for the infant, and provides important protection from diseases through the mother's natural defenses.

Description

Early in a woman's pregnancy her milk-producing glands begin to prepare for her baby's arrival, and by the sixth month of pregnancy the breasts are ready to produce milk. Immediately after the baby is born, the placenta is delivered. This causes a hormone in the woman's body (prolactin) to activate the milk-producing glands. By the third to fifth day, the woman's breasts fill with milk.

Then, as the baby continues to suck each day, nursing triggers the continuing production of milk. The baby's sucking stimulates nerve endings in...