What Does This Ultrasound Result Post Abortion Indicate?

I had an abortion 2 weeks ago. I had an ultrasound yesterday and the result was: There is Hetergen solid mass (size 13 mm * 16 mm) in my endometrial Cavity, which is a sign of placenta retention.Since my bleeding has not been stopped yet.Is it okay for me to wait till it stopped or should i take misoprostol or surgical procedure is required.Would you please help me through this.Thanks