The Stages of Lactation

Lactogenesis I

• Lactogensis I, the first stage of lactation, marks the beginning of the lactation process. Beginning in your second trimester -- often around 16 weeks -- your breasts start to produce colostrum. This milk is thicker and stickier than the milk you may expect your body to produce, and it's often yellowish in color. Colostrum is high in carbohydrates, protein and antibodies, which is important for your newborn. This milk produced during the first stage of lactation will serve as your baby's nutrition for the first several days of his life.

Lactogenesis II

• After you deliver your baby -- and your placenta -- your body shifts into the second stage of lactation, Lactogenesis II. About 30 to 40 hours after birth, your milk increases in volume. Hormonal changes -- specifically, a drop in progesterone -- after birth promote an increased volume of milk. The Clinical Lactation journal reports that, on average, a mother's milk comes in around day four of lactation.

Lactogenesis III

• Lactogenesis III, the third phase of lactation, is typically the longest-lasting stage. It begins when your milk regulates after birth and continues throughout your breastfeeding experience with your child. Around 10 days postpartum, your milk supply is maintained until you begin the weaning process. This period lasts for however many months -- or years -- you choose to nurse your child. During this stage, your milk production fluctuates depending on your baby's appetite and nutritional needs.

Lactogenesis IV

• You initiate the final stage of lactation, Lactogenesis IV, when you begin the weaning process. Breast inovulation begins to occur as you minimize breastfeeding, resulting in reduced milk production. This stage can last for a matter of days or a matter of months, depending on how you choose to wean your baby. At the end of this stage, you no longer produce milk, thus ending the lactation process.