Confused! Please help

Any input is appreciated! 
I have long cycles that range from 45-60 days. I have been charting my bbt for 3 months and it does seem as if I am ovulating. I am wondering if low estrogen or progesterone would be the cause of such a late ovulation? I am on cycle day 49 and just now ovulated. 
At first I was thinking it was a lack of estrogen but during my last cycle I devolved an ovarian cyst and read that excess estrogen can cause them. 
I am on cabergoline for elevated prolactin levels but recent blood work shows that my level is in normal range.