I'm on my first period after a month of being off the birth control pills. My cycle has been on since Monday September 12 and I usually have a 7 day period so my last day should be either today or tomorrow. Once it goes off what are my chances of becoming pregnant? I only took bcp for one month to start my period back after I had been off depo for 6 months and didn't have a period. I haven't taken bcp since August.