How do natural methods of family planning work
From Audiopedia
There are also 3 methods to avoid pregnancy that do not require any devices or chemicals (as with barrier methods) or medicines (as with hormonal methods).
The methods are:
IMPORTANT: Natural methods of family planning do not protect against STIs, including HIV. If you use any of the natural methods listed in these pages, you still need to think about ways to protect yourself from these diseases.