Can A Cyst On Ovary Cause Irregularity In Periods?

I just had a doctors appointment after getting the results from an ultrasound. The doctor told me I have a cyst on my ovary which could be the reason I had a period for a month and a half which has now stopped. I am waiting for results on an MRI that I had done for tailbone pain that I have been dealing with for a year now. Can these be related?