The breast development experience how many not corresponding period?
The breast is the common feature of the mammal, generally become to the growth, zygomorphy, bilateral symmetry.Mankind mammary gland only have before the thoracic cavity of 1 rightness, come from ectoderm.After be born, breast development experience infancy, adolescent, sexual maturity period, gestation period, lactation period and menopause’s etc. not corresponding period.In the each one not contemporaneous variety, the machine ketone body level difference of the endocrine, internal secretion hormone is very big, is affect by it and breast development and physiology function are also each to have special features.
The kid is mid-term, expect at the new-born infant, can get into a small infant in vivo through a placenta because of the maternal female sex hormones, cause mammary gland tissue hyperplasis, past have 60% the or so new-born infant around 2~4 days appear the induration of the size of nipple next 1~2 cm after be born, also a little amount human milk kind material secret, along with the gradual metabolism of maternal hormone, this kind of phenomenon can 1~3 turnovers disappear by oneself after be born.Here what to need to be point out BE, absolutely not to and by hand squeeze nipple, the in order to prevent results in infection.Our country some regions spread thus of customs, namely the birth of new-born infant all squeezes nipple behind, otherwise thinking will make nipple hollow, this kind of understanding isn’t scientific, the way of doing also can’t take, result in the reason of nipple depression be the embryo period mammary gland dysplasia, but not because of DOing not squeeze nipple.At baby’s infancy, the mammary gland is basically placed in a “quiescence” condition, the ceruminous gland ketone body presents to back to go sex mutation, the male compare of the female be more complete.
From the adolescent beginning, under the influence of various endocrine, internal secretion hormone, the female breast got into the physiology in the whole life development and function activity the most active period, until menopause.After experiencing adolescent, the tissue structure of the mammary gland has already tend perfect, got into a sexual maturity period mammary gland.In each menstrual cycle, along with the periodic variety of ovary endocrine, internal secretion hormone, the mammary gland tissue also takes place to go round and begin again of hyperplasis with return to old of variety.Gestation period and lactation’s expect is a reproductive life women of special physiology period, at this time in order to adapt this kind of special physiology need, the mammary gland also a series happenned variety.From the menopause beginning, the ovary endocrine, internal secretion hormone reduces gradually and the breast physiology activity gradually dies down.
