Breast development is not able to express milk. Lactation occurs after childbirth and requires conditions.
The production of milk depends on the delivery of the placenta after delivery, the mother’s estrogen and progesterone plummet, the secretion of lactation hormone and oxytocin increases, milk production begins to abound, and the breasts are full.
During puberty, the body secretes estrogen and progesterone, which awakens the sleeping breasts and leads to the development of mammary glands. Estrogen stimulates the growth of milk ducts and fibro-fatty tissue, and progesterone stimulates the development of lobular tissue and areola, and does not have the involvement of prolactin and oxytocin to initiate lactation.
Adolescent breast development, there may be nipple watery overflow, mostly caused by the expansion of the milk ducts, not milk, usually can subside by itself, no need to worry too much; such as blood overflow, please need to promptly ask a professional doctor to rule out breast disease.