The breasts happen to be one of the finest assets of a female body and almost every woman out there would constantly dream of having perfectly shaped breasts that do wonders to highlight their figure.
Have you ever wondered what breasts are made up of inside or how you manage to give milk to a newborn all of a sudden when you have never lactated before or how your breasts suddenly start increasing in size after puberty and delivery? The answer to almost all these questions is ‘hormones’.
The Developmental Cycle of Breasts
What exactly are breasts made of? If you think they are just skin and more skin, you are wrong. Beneath the surface, breasts are actually made of fatty tissues that respond, react to and are stimulated by the breast developmental hormones.
It is only during puberty that the breasts start to develop wherein the cells inside the breasts start to divide and proliferate, leading to an increase in breast size. After childbirth, the breast cells proliferate further and then transform into specialized cells that produce and secrete milk. And it is at this juncture that the breasts are said to be fully matured. With the stop of breastfeeding the breast cells (the specialized ones) die and the breasts come back to their original size (before pregnancy).
How do all these changes happen in the body you ask? Simple, the answer is ‘Hormones’.
Essential Hormones for Breast Development
The body is filled with plenty of hormones that aid it in its normal day to day functions. Some of these hormones that circulate within the body constantly are responsible for the development of breasts right from puberty to delivery and afterwards too. And these five hormones include:-
Estrogen and Breast Development
This particular hormone is responsible for the division and proliferation of breast cells during puberty and afterwards. Accordingly, during puberty, the ovaries would start to produce high levels of estrogen.
The estrogen thus produced will stimulate the formation and deposition of fat inside the breast’s connective tissues, thereby leading to an increase in breast size. After puberty, the breasts would continue to increase during every menstrual cycle. Accordingly, the estrogen levels in the body increase rapidly during the beginning of the menstrual cycle (first half) each month. This would lead to an increase in breast size.
After ovulation, the estrogen levels would decrease and the breasts would also decrease to their original size. In case of pregnancy, the estrogen levels keep on increasing throughout the pregnancy in order to prepare the breast for lactation and breast feeding.
Progesterone and Breast Development
Progesterone is another steroid hormone in the body that helps in breast development. It works along with estrogen to make sure that the breasts increase in size and function properly. Accordingly, the progesterone levels in the body increase during the second half of the menstrual cycle. By this time, the estrogen levels in the body would have dropped.
The progesterone produced at this juncture helps to maintain breast health and proper development of the same in the absence of estrogen.Again during pregnancy, the increased levels of progesterone in the body start stimulating the formation of milk glands for lactation.
While the estrogen works to enlarge the breast tissues, progesterone makes sure that these tissues function properly and contribute to overall breast development. During pregnancy, the progesterone levels remain high in order to stimulate the development of milk glands and buds to facilitate lactation and breast feeding after childbirth.
Prolactin and Breast Development
This particular hormone originates from the pituitary gland in the brain. The hormone is responsible for the stimulation of lactation and milk secretion from the breast. The levels of prolactin usually increase during the first few days of the menstrual cycle and causes miniscule changes to the breast tissue.
During the first few weeks of pregnancy, the prolactin levels in the body remain low while the high levels of estrogen and progesterone contribute to breast development.
Once the levels of these two hormones decrease and the breast is ready for milk production/secretion, the prolactin levels start increasing. Stimulated by the suckling action of the child, the prolactin starts acting on the mammary glands of the breast and thus aids in milk production/secretion post pregnancy.
Oxytocin and Breast Development
Oxytocin also originates from the pituitary gland in the brain and is usually found in high levels in the body during the second trimester of pregnancy, mainly the fifth and sixth months. The hormone is responsible for stimulating milk production inside the breast. After childbirth, the elevated oxytocin levels would send appropriate signals to the breasts to start lactating in order to start breastfeeding.