I used to always get heartburn on an empty stomach all throughout my pregancy, so had to eat more often, and milk became my best friend!
for Me though, after i had Ben, i found out a had great big gallstones and had to have my gallbladder out 4 months after i had ben. BUT I'm not saying that you have gallstones, dont worry, that was just the case for me. isnt heartburn due to lack of stomach acid?