C.M. is a 28-year-old woman with a long history of dysmenorrhea managed for many years with oral contraceptives. She stopped taking the pill 8 months ago in anticipation of becoming pregnant with her first child. Having stopped the contraceptives, C.M. has been experiencing diffuse abdominal and back pain beginning about a week before menses. Her periods have become very heavy. An initial diagnosis of endometriosis is made.