Good day. 3 years ago I did an ultrasound which showed an enlarged left ovary of about 7-8 cc in volume and I was not treated for it as it was not deemed worrisome. Last week because of severe menstrual cramps, I did another which showed the left ovary grew to about 36 cc in volume while the right is now 18 cc in volume, both with cysts. I have been diagnosed with pcos by my doctor but I would like to know what caused my ovaries to get so much bigger over the last 3 years? Is it that more and more cysts appeared and are filling up my ovaries? A couple friends have pcos but their ovaries are the normal size.