Having briefly summarized the physiology of lactogenesis and gactopoiesis, the authors stress the fundamental role played by prolactin. In this context, they suggest medical treatment intended to improve mammary function in cases of deficient lactation. Two different types of treatment were tried: direct administration of prolactin or administration of antidopaminergic drugs capable of increasing endogenous prolactin production. In addition to confirming once more the usefulness of early physiological stimulation by suckling, experience in a group of puerperae showed that treatment apt to increase prolactin serum levels was the best therapeutic choice.