I had been chartign for 6 months and never had a temp increase after ovulation and my
luteal phase was never longer than 8-9 days. I also had breakthrough bleeding/spotting
for several days before AF, and AF was very heavy, long, and painful. After doing a lot of research, I felt fairly confident that progesterone was the culprit, and I started using an OTC progesterone cream after ovulation. I got pregnant that same cycle.