Natural family planning — or fertility awareness-based methods—involve tracking your menstrual cycle to determine when you are ovulating, so you can avoid having sex on the days you are most fertile.

There are several methods to track your cycle. Although one of the least reliable methods of birth control, these can be used in combination with other methods, like condoms or withdrawal, to increase effectiveness:

The Temperature Method – You take your Basal Body Temperature (BBT) every morning before you get out of bed and track it on a fertility awareness chart.

The Cervical Mucus Method – You check and track your cervical mucus every day. You can get pregnant from the onset of your secretions until 3 days after it stops. You are the most fertile when your cervical mucus is clear, stretchy, slippery and wet.

The Calendar Method – You chart your menstrual cycle on a calendar to determine the length of your cycle and the days when you will be the most fertile