Need some help regarding Bacterial Vaginosis

Hello, Everyone,

I'm sorry if this has been asked/posted before. (My googlefu has failed today).

I had a case of Bacterial Vaginosis two months ago. I noticed after my period that I had more of a discharge than normal and it smelled horribly. I went to my Doctor after about a week when it had not gone away. (I know every once in awhile I'd have a heavier discharge and it would smell for a day after a period but would go away). My doctor put me on Antibiotics for the week. I completed the course, and lo and behold, I didn't smell and the discharge was back to normal.

Cue right after my next period. Same discharge, same fishy smell. Didn't go away after a day or two, so I called the doctor and she prescribed me more Antibiotics . After the seven days of treatment, I was good to go.

Now, I was doing good for three weeks, then I had my period again, and it's been a day or two after my period has stopped and I've had more of a discharge again, and it absolutely reeks again.

My periods are normal. I'm on the birth control pill called Portia, been on it since September. I have only one partner. (My fiance).

So has anyone else had this happen? Why does it keep coming back right after my period? I'm going to be calling up my doctor again, but unfortunately the office isn't open until Monday.

Thanks in advance :)