For those using the Sympto-Thermal Method of NFP, it is important to get a usable temperature pattern and so it is very important to take your temperature pattern at roughly the same time each day while you are trying to establish infertility. You can take it up to 45 minutes before or after your usual time without considering the temperature disturbed, provided all temperatures are taken before 7:30 a.m. Once you are in the post-ovulatory infertile time, you can relax regarding this point.