Fertility awareness (natural family planning) is a way of predicting which times of the month a woman is fertile and more likely to get pregnant. 

The method involves recording signs of fertility such as body temperature, thickness of fluid in the vagina, and calculating fertile times from menstrual cycle dates. 

Teaching from a qualified fertility awareness teacher is recommended.

Fertility awareness can be very effective if followed correctly.



  • Non-hormonal method
  • There are no side effects
  • Helps women understand their own bodies better
  • Skin to skin contact
  • Acceptable in most religions and cultures
  • Can be useful when trying to become pregnant


  • It can be tricky to learn, and takes a few months to monitor patterns
  • May have a higher risk of pregnancy
  • Daily monitoring is needed (temperature, thickness of fluid in the vagina)
  • Illness, stress or travel might make it hard to interpret records
  • Unprotected sex should be avoided on the most fertile days
  • No protection from sexually transmitted infections
  • Both partners need to be committed to use this method
  • To work best it should be taught by a qualified fertility awareness teacher

Are mobile phone apps reliable?

There are hundreds of apps for monitoring periods. Fertility awareness apps indicate likely fertile times, and times when it is safer to have unprotected sex. Most apps are unregulated and have never been properly tested, so we don't know how reliable they are.

To rely on fertility awareness, it is important to record two or more signs of fertility. For example, the Natural Cycles app records morning temperature as well as period dates. There has not been enough research yet to know how reliable this app is.  

Apps which just record periods are not reliable enough.

Which other methods are hormone-free?

If you're keen to avoid hormones, contraception methods like the copper coil or diaphgram might suit you. You have skin to skin contact with a partner with these methods.

What's right for you?

Good to know

Fertility awareness requires careful monitoring of the body's patterns to work well as a contraception method. 

How much effort is Fertility Awareness?

Women need to pay close attention to their bodies and to patterns over time. They record body temperature first thing in the morning, feel the thickness of fluid in the vagina, and work out when they are likely to have released an egg (ovulated) based on the length of their cycle. Body temperature and fluid in the vagina change depending on where a woman is in her cycle, and therefore whether she can get pregnant if she has sex at that time.  Fertility awareness is more effective when two or more of these patterns are monitored together.

A woman needs to record patterns over at least three months before she can start to predict her more or less fertile days.  If a women’s periods are irregular, or if she has recently stopped using a hormonal method of contraception, it takes longer to be able to predict fertile times accurately. 

There are fertility charts and mobile phone apps that can help track the changes and to chart the more fertile and less fertile days. It's very important to monitor at least two signs of fertility - apps which just record periods are not likely to be reliable.

Male partners are also involved, since they will need to use condoms or avoid penetrative sex at some times of the month. 

How effective is Fertility Awareness?

Fertility awareness is generally not as effective as hormonal or long-acting methods of contraception. 

When used perfectly, fertility awareness is between 91% and 99% effective, meaning that if 100 women used fertility awareness for a year, between 1 and 9 of them would become pregnant. It takes commitment to use the method effectively, but it is a reliable method when used with attention to detail.  However, allowing for the ups and downs of life, the method is around 76% effective, meaning that if 100 women used fertility awareness for a year, around 24 would become pregnant. 

How does it work?

Fertility awareness works by calculating when it's safer to have sex (when pregnancy is unlikely), and when to avoid penetrative sex or use another method (like condoms).

What's right for you?