Any other mommies have a under active thyroid? And took this type of birth control to regulate out your periods? so you can Conceive. If so how long were you on it for to regulate your periods and how long did it take for you to get pregnant after stopping it? I know everyone is different, just trying to get a Estimate on how long it might take for me to get pregnant with baby number 2. We been trying for a year and no luck because of my irregular periods. so my doctor put me on the pill to regulate my periods, i only been on it for a month.