trackle is based on the rules of the symptothermal method according to Sensiplan. The symptothermal method is the safest method of natural family planning (NFP) and has a theoretical Pearl Index of 0.4 in method safety and is thus – just like the contraceptive pill – below 1.

Detailed information about the Pearl index is available here.

Unfortunately, no method of contraception can provide 100% safety – as with all methods of birth control trackle, too, has some remaining risk of becoming pregnant from unprotected intercourse. 

trackle digitises the rules of the symptothermal method and helps you to use it more safely and easily. However, we still recommend that you learn about the rules of this method of contraception. The book "Natural & Safe The Handbook: Family Planning with Sensiplan" is ideal for this.