How your breasts produce milk
In just nine short months, your body nourishes and grows a fetus into a baby. Then, it produces food for this new baby. Here’s how it’s done:
Changes before the birth of your baby
Long before your baby’s birth, your body silently prepares you to be your baby’s primary source of nourishment. During pregnancy, hormones stimulate the mammary glands of your breasts to produce milk. The whole process starts in your brain, where your pituitary gland secretes two special hormones:
- prolactin, which prompts your body to start producing milk
- oxytocin, which signals your breast to release the milk as your baby sucks
By about the sixth month of your pregnancy, you’re ready to make milk. Your breasts may increase in size.
Changes after the birth of your baby
Prolactin and oxytocin are produced in response to the last stages of pregnancy and labor and then later by nipple stimulation during breastfeeding. Here’s how this works:
- Prolactin stimulates the glands in your breasts to produce milk.
- Breastmilk moves into your milk ducts, where it pools until you’re ready to feed your baby.
- During breastfeeding, as your baby nurses, the nipple stimulation from her sucking causes the release of oxytocin, which opens the channels, letting the milk flow.
The breastfeeding clock
Breastfeeding is a natural process, but both the baby and mom need to learn how to make the experience productive and comforting. Here’s an idea of what to expect:
Week 1: During the first three to four days after you give birth, your breasts secrete a thick, yellowish, translucent fluid called colostrum, which is high in protein, vitamins, minerals, and antibodies. Frequent, short feedings these first few days help both you and your baby adjust to breastfeeding and increase milk production.
Transitional milk comes in after about three to five days of breastfeeding. It marks the change from colostrum to regular breastmilk. As the milk comes in, your breasts may become very full and feel tender. Continue to breastfeed every two to three hours; don’t skip feedings or prolong the time between feedings. Consistency is important to help your body establish milk production and to synchronize with your baby’s needs.
Week 2: By this time you may feel more comfortable with breastfeeding. The latch-on and positioning procedures should be easier, and milk production should be well on its way.
Week 6: By the sixth week, you’ll feel physically stronger and should be reasonably recovered from the birth process.
Week 12: At this stage, you should be through the period of adjustment and feel fairly comfortable with breastfeeding.
During breastfeeding your body uses whatever nutrients are available to make breastmilk. You don’t need to worry if your diet isn’t perfect, but be sure to eat a healthy diet whenever possible.