Hi, I've Been Having An Out Of The Blue Stabbing

Hi, I've been having an out of the blue stabbing pain in my pelvic area. It hurts so bad that I normally hold my breath and hang tight till the pain goes away...its extremely painful. I've had 3 children, 2 by vaginal birth, 1 by csection. About 13 years ago I had a hysterectomy, due to cervical cancer, but was able to keep my ovaries. What could this pain be?