Long cycles then short, then long again?

Was that your first time charting BBT? If so, I'd continue charting the next few cycles to see if O is consistently occurring. If you find that you do O each cycle, is it on the same day? It probably won't be and that would be the reason your cycle length varies. In women with consistent cycle lengths, they tend to O on about the same day each cycle. For women with varying cycles, they may still ovulate, but not at the same time. If you are Oing, though, and there is at least 10 days between ovulation and your next period, then things are probably ok...you'll just need to time things very well in order to conceive. If you find you are NOT Oing, either in your shorter or your longer cycles, then you may need some istance. It's not unusual or a problem to miss up to two eggs a year, but if you have more than 2 cycles in a 12 month period without ovulating, then that is considered a fertility issue, so speak to your doctor about it.