So I had my prolactin level checked and it is 31. My son is 11 weeks old, I nurse on demand 24 hrs. a day, we cosleep, he's gaining weight, however at the low range of normal. We always suspected low supply, but couldn't really confirm it. Does anyone know why my prolactin is so low or what can I do about it? Normal prolactin for a lactating women is over 100. Today I had to supplememnt frozen breastmilk my poor son sucked for over an hour....no let down. I tried switching sides and no luck, so I used the sns to supplement. Help.....what is going on? Thanks in advance.