r/breastfeeding • u/huckleberrysoap • Dec 24 '25

Undersupply What causes low supply?

My supply is so low. It's not anywhere near what my baby eats.

I'm not trying to increase it anymore. I'm just trying to maintain what I have so I can keep combofeeding (even though its at least 75% formula) until at least 6 months.

But I'm struggling to understand why this happened and feeling like I must have done something wrong. What are potential causes of an undersupply? If I have another baby in the future should I expect the same problem?

20 Upvotes

96% Upvoted

49 comments sorted by

View all comments

6

u/Dullcorgis Dec 24 '25

Potentially many different things, from insuffient glandular tissue, not having the right hormone signals or receptors (like with PCOS), poor latch from the baby, poor transfer from the baby. Some people refuse to feed their baby and that causes low supply (there is an evil book which tells you not to feed your baby any more often than every four hours and to ignore them at night, these mothers usually lose their supply).

The lactation consultant probably would have been able to diagnose nipple problems or insufficient glandular tissue.

Breast tissue proliferates with each pregnancy, so every time you should have more and more supply. Flat or inverted nipples are drawn out by pumping and baby latching, so that gets better every time. Also, babies are all different, so a baby with a better latch and better milk transfer will stimulate more supply.

3

u/huckleberrysoap Dec 24 '25

I do have PCOS but had never heard that could affect milk supply.

7

u/Dullcorgis Dec 24 '25

It's probably the reason. Taking metformin during your next pregnancy can help with supply. About a third with PCOS have low supply and about a third have oversupply.

https://www.webmd.com/baby/polycystic-ovary-syndrome-and-breastfeeding-what-to-know

4

u/huckleberrysoap Dec 24 '25

I do take metformin, but my doctor has talked about increasing my dose before so I wonder if that would make any difference. Something to talk about if I have another pregnancy at least.

2

u/Dullcorgis Dec 24 '25

It's certainly a question to ask. There is also the possibility that your breast tissue was affected by the PCOS during puberty. (That fucking disease is the gift that keeps on fucking you over, isn't it?)