In plain words
Lactogenesis I is the first stage of milk production. It happens during pregnancy, and it is usually complete by the middle of the pregnancy. The milk-making cells in the breast mature, and the ducts grow and branch. The cells start to make , the early milk. Hormones such as , estrogen, and progesterone drive this work. High progesterone during pregnancy keeps the breasts from making large amounts of milk yet. That is why many people do not leak milk until after birth. Some people do leak colostrum during pregnancy, and many do not. Both are normal. Lactogenesis I is part of pregnancy, not a sign of how much milk you will make. The next stage, , is when milk volume rises after birth.
The deeper version
Lactogenesis I, or secretory differentiation, is largely complete by mid-pregnancy under the combined effects of prolactin, , cortisol, insulin, and estrogen. These drive ductal elongation, alveolar formation, and acquisition of secretory capacity in lactocytes. High progesterone and its receptor signaling restrain copious secretion and keep open, so colostrum is rich in sodium and chloride and low in lactose. Neville and colleagues (2001) described this sequence. Lactogenesis I is not routinely measured clinically. Antenatal studies show that some pregnant people produce colostrum before birth, while evidence on whether antenatal expression changes later outcomes is mixed. The controversy concerns whether antenatal breast preparation affects later supply, which trials have not clearly shown.
Where it comes up
- Colostrum and the first days before milk comes inFeeding Your Baby
- Feeding prep: what nobody tells you while you're pregnantGetting Ready for Birth
- How breastfeeding works: supply and demandFeeding Your Baby
- Hand expression and collecting colostrum before birthFeeding Your Baby
What mothers here say about lactogenesis I
No one has posted under this term yet.
Sources
- Neville MC, Morton J, Umemura S — Lactogenesis: the transition from pregnancy to lactation. Pediatric Clinics of North America, 2001