I have taken mononessa for about four and a half months, and have gained roughly 15-19 pounds. i recently had a period about two weeks ago. a couple concerns i have are any chance i could be pregnant? and is it likely i'll lose the weight once i change ba

Unlikely: In fairly large studies, birth control pills are generally only associated with weight gain of 1-2 lbs. So 15+ lbs is unlikely caused by the pills. That being said, there are always rare cases, so stopping the pills (and perhaps using condoms for a bit) should drop the weight pretty quickly if they're the cause. Pregnancy on the pill is also uncommon, but a home pregnancy test can answer that!