Mid-cycle bleeding and pain- on pill

I'm going to try to be as detailed as possible, sorry if anything is irrelevant.

So I've been on YAZ since July of 2009, a few months back the pharmacy switched me to  a generic version but after not feeling well that month I went back to the Yaz, at this point I've been back on it for three months.

Anyways I've recently started bleeding and I have 9 days left before beginning my inactive pills. So basically I've already taken 15 pills this month. The bleeding is much more like a normal period than just some spotting. I have not missed any pills and have generally taken them within an hour of each day when not taken at exactly the same time. Nothing abnormal or strange with how I've taken the pills, exactly like every other month.

Along with the bleeding I'm experiencing moderate to severe pain/ crampy feeling especially on my right side.

Back in April I went to ER for abdominal pain and was told it was Mittelschmerz- I was and had been on the pill for some time before this incident (started BC pills in Sept 2008) and it had only been about a week from my last period at the time. I didn't think that was possible but I then again I'm not a Dr.

In case it matters the last time I was sexually active was the day before the irregular / midcycle bleeding started.

So what can be causing the mid-cycle bleeding and pain? Is it something I should be worried about? I'm I still protected against pregnancy or should I be using a back up method?

Thanks.

[Elaine Brown, MD]

Hi!
I suspect that the breakthrough bleeding is related to the change in the pills -- from Yaz to generic and then back again.  Even though you have taken them properly, the changes in the product may have been enough to cause bleeding.  If you have not missed any pills, you should be "OK" as far as contraception goes. The bleeding would probably stop pretty easily if you increased to two pills per day for a short time -- naturally you would want to do this with your doctor's permission and knowledge because you will run out too soon otherwise.  Oh, and I ALWAYS recommend a pregnancy test any time there is unusual bleeding -- just to be safe.
Good luck!
Dr B