I'm on cycle day 26 with no sign of ovulation. I've been using OPK's since cycle day 10. I have long cycles...40-45 days. I'm getting nervous that I may be ovulating too late or some months maybe not at all. I had an early MC 2 years ago and now that I'm researching ovulatin think that my late O may be the cause. Apparently women who O late have already began shedding their uterine lining which makes it harder for implantation.