Question on Breast Milk Production

Students General Students


OK, I have never asked for help on a class assignment before, but my lab book does not go with my A&PII class book and I cannot find the answer to this question in either.

When does milk production by the breasts usually occur?

1) immediately after birth

2) on the second day

3) by the third or fourth day

I know that the exit of the placenta after birth and the decrease in progesterone and estrogen and increase in prolactin make the breasts produce milk, but when by what day does the milk production actually occur? Is it right after the placenta is expelled or a few hours?

I found on a website that "full" production occurs on the third day but that seems like a long time. What does the baby eat on the first two days?

Any info. you guys may have would be appreciated.


391 Posts

3rd or 4th day, oy does it :eek: The body produces colostrum (sp?) until milk comes in. :)


245 Posts

Milk production begins someplace between 48 and 96 hours after delivery, and is denoted by breast engorgement and sometimes malaise or 'milk fever'.

Prior to the milk coming in, the baby receives colostrum, that thick, clear yellow liquid which has a high fat and carotenoid component and helps move the meconium along. Newborns actually don't need to nurse that much during the first few hours and days after birth--they were fed through the umbilical cord right up until the moment it was cut.

Check out "The Breastfeeding Book" by William Sears, M.D. and Martha Sears, R.N. for more info and to learn everything you could possibly hope to know (and some stuff you probably don't want to know) about breastfeeding.


1,326 Posts

Ahhh, so let me get this straight.

The breasts are allready full with colostrum before and at birth, then after birth and when the placenta is expelled and hormone levels change the breasts begin production of breast milk (3-4 day).

So, for the first couple days the infant nurses and gets the colostrum and then by the third or fourth day gets the "milk".

Just making sure I get this all. Women's health is very interesting to me so I want to make sure I understand it all. Usually our lab book is very good but for some reason the questions went straight from the anatomy of the reproductive system and straight into pregnancy but it doesn't cover any background information at all on pregnancy or conception.

It's really odd and our A&P book doesn't have a chapter on Conception. Just genetics and menstral cycle. Hope this isn't an indication of the rest of the chapters.

Thanks for your help,



245 Posts


The breasts produce colostrum as the baby suckles, not in advance of the suckling. A small amount of colostrum is produced before birth (starting in the late second trimester) , but the vast majority of colostrum (and later, milk) is produced simultaneously with the act of nursing--this is the letdown or milk-ejection reflex (MER).

It sounds like your A&P book is missing a lot on the mechanics of breastfeeding. Again, check out the Sears' book.



187 Posts

Maybe an OB/GYN book would be a good reference instead of A&P

This topic is now closed to further replies.

By using the site, you agree with our Policies. X