I just wanted to share a little bit of my ovulation/cycle/testing experience with you ladies. I know I am older and much of my issues could be age related, but some of this information may help some of you. I thought I had regular cycles, a little shorter than normal 26-27 days but normal none the less. Once I started bbt charting I realized I ovulate later- around cd 16-17 and learned I have a short 10 day luteal phase. I began using opks along with bbt and always "came close" to a positive, but always had a thermal shift so I just chalked it up to missing my surge on the opks. One particular lab testing cycle stands out, though.. I got my first blaring positive on an opk, clear thermal shift on bbt, and my labs showed no ovulation.. i was gutted. How could an opk and bbt both happen but no O? Turns out that i have low ovarian reserve (age) and weak ovulation. my body gears up to ovulate but it is so weak - hence the low progesterone and short luteal phase. Clomid therapy is supposed to help.. anyway, sorry for the paragraph, but I thought I'd share my experience.