Natural contraceptives are methods based on sexual abstinence following the periods of ovulation of the woman. This results in the couple avoiding intercourse on the most probable date of evolution, at least for 8 days in the middle of the menstrual cycle.
Natural contraceptives are only recommended for women with very regular menstrual cycles, which make it possible to calculate fertile days reliably from month to month. Otherwise, and especially if an unwanted pregnancy is to be avoided, other methods that are more effective may be considered.