I have had abnormal monthly bleeding for 3+ yrs. I tried birth control pills, had a hysterosonogram which showed polyps and fibroid. I had a dnc and the abnormal bleeding stopped for 3mths, then it came back. Md stumped. Ideas?

Dysmenorrhea. At age 30, the likely causes are the cervical polyp and/or the fibroid. These tend to bleed and heal and bleed again. If the D&C debrided all the tissue, then it is a mystery. Possibly, the procedure left behind some abnormal remnants of the fibroid, and may need to be re debrided. Sometimes, ocs are prescribed for individuals who continue to have abnormal periods. If that doesn't work, D&C again?
Several options. If the periods are regular but heavy more likely the cause is something physical with the uterus, such as from the fibroid or adenomyosis. Treatment is usually a procedure such as removing the fibroid (abdominally or through the vagina, which depends on size and position) or hysteroscopy with ablation or uterine artery embolization. Speak with a gynecologist.