So I chart and use a diaphragm during my fertile time. (Which means I track my BBT to tell when I ovulate so I know to avoid having sex at that time.) I didn't chart this month because I had knee surgery and it was just harder to get up in the mornings. But here's my question - I am on cycle day 40 with no period. I do not believe I am pregnant because my temp is still below my post - ovulatory temp which means I haven't even ovulated yet. Can narcotics (Lortab, Percoset) cause me not to ovulate and therefore my period to be late? I have been on quite a few because of the surgery. Just curious if anyone else has had this problem...