I charted for my first month using a thermometer that only went to 1 decimal place - I deemed the first cycle annovulatory because I couldn't detect ovulation (OPKs don't work for me because I have PCOS), however, in the second month I changed to a 2 decimal place thermometer and noticed a huge difference. I was able to detect ovulation and fell pg that cycle (am currently 18 weeks pg).

I would definitely invest in a 2 decimal place thermometer if you can... you will notice so many differences in your charts - often it is the miniscul differences (like the 0.02 changes) that really help pinpoint ovulation etc.

best of luck with your TTC journey