How does natural family planning work?

Natural family planning works by observing and recording your body’s natural signs or fertility indicators on each day of your menstrual cycle (the first day your period starts to the day before your next period).

The main indicators are body temperature, cervical secretions and the length of your menstrual cycle. Monitoring these indicators will help you identify your fertile time which usually lasts 8-9 days of each menstrual cycle.

What are the advantages?

  • Natural family planning can be up to 99% effective if followed according to instructions
  • Being more aware of your fertility can help you plan a pregnancy as well as avoid it.
  • It does not involve any chemicals or devices
  • There are no physical side effects

What are the disadvantages?

  • It can take 3 – 6 menstrual cycles to learn the method effectively
  • You have to keep daily records
  • You need to avoid sex or use condoms during your fertile time
  • You are not protected against sexually transmitted infections

Where can I get more information about natural family planning?

You need to find someone who can teach you natural family planning and your GP or local sexual health clinic may not offer this.  You can get more information from:

Family Planning Association (FPA) at

Fertility UK at