In this article we will discuss about the process of lactation, explained with the help of suitable diagrams.  

The hormones which influence the development of breasts are:

a. At puberty, it will be estrogen and progesterone. In addition to these, some of the other hormones which are also required are: thyroxine, growth hormone, Cortisol and insulin.

b. During pregnancy, it will be estrogen and progesterone which are secreted in large quantity either from corpus luteum or placenta. Apart from these, the human chorionic somatomammotropin (HCS) secreted by placenta also is responsible for growth of breasts. There is no lactation during pregnancy because, progesterone level is high and it inhibits the release of prolactin.

c. After delivery, since the concentration of progesterone falls earlier than the estrogen, prolactin secretion starts and lactation commences in about 1-3 days. During this phase, suckling is the most effective stimulus that brings about secretion of prolactin.

“The breasts were more skillful at compounding a feeding mixture than the hemispheres of the most learned professors brain”—Oliver Wendell Holmes

Hormones Influencing Lactation:

1. Prolactin:

Suckling of breasts not only brings about release of oxytocin (Fig. 7.21), it will also stimulate the secretion of prolactin. For both the hormonal secretions, it is the neuroendocrine mechanism that is involved.

Myoepithelial Cells in Breast and Neuroendocrine Reflex

2. Some of the other hormones influencing lactation are thyroxine, and growth hormone. ACTH and glucocorticoids are necessary for maintenance of milk secretion which is known as galactopoiesis.

Emotional conditions, like cry of the baby and condition reflexes, also play an important role in lactogenesis.

Advantages of Breastfeeding:

1. Infant gets a well-balanced diet.

2. Stimulation of nipple releases oxytocin. Oxytocin brings about involution of uterus and size of uterus is reduced following parturition.

3. During the time of breastfeeding, ovulation is inhibited. This is because prolactin inhibits the release of luteinizing hormone.

4. The infant gets some amount of passive immunity since milk contains some of the antibodies.

5. Since it is directly coming from mammary gland, contamination is less and chances of child suffering from infantile diarrhea is minimized.

6. It builds psychological bond between mother and child.