Understanding Lactation Hormones During Pregnancy: A Comprehensive Guide

1. Progesterone: This hormone, which is produced by the corpus luteum during pregnancy, helps to stimulate the growth and development of the milk glands.

2. Estrogen: This hormone, which is also produced by the corpus luteum, helps to increase the number of milk-producing cells (alveoli) in the breasts.

3. Human placental lactogen (hPL): This hormone, which is produced by the placenta, helps to stimulate the production of milk by the breasts.

4. Prolactin: This hormone, which is produced by the pituitary gland, is responsible for the actual production of milk by the breasts. Prolactin levels rise during pregnancy and reach their peak just before birth.

5. Oxytocin: This hormone, which is also produced by the pituitary gland, is responsible for the ejection of milk from the breasts. Oxytocin levels rise during breastfeeding and cause the breasts to contract and release milk.