Hello, my last period was on December 4/09. I was on birth control pills and my husband and I decided we wanted to get pregnant so I stopped taking the pills 4 days after I started them. I had breakthrough bleeding on December 14th, that lasted 4 days. We've been having unprotected sex for about 8 days now and my period was supposed to come yesterday. I was just wondering what the chances are that I may be pregnant, or if my cycle is off due to stopping the pills mid cycle.

Well, I'm not an OBGYN, we don't have any on this site, but I'm the next best thing. I'm an OB nurse.

So, you only took birth control for 4 days when you decided to try for a baby? If that's so, the breakthrough bleeding could be causing your period to be late this month.

However, your period was only supposed to come yesterday. One day late is not considered late even for the most regular woman. Wait a week and see if your period comes. If not, then try taking a HPT using first morning urine.