beginning of content

Fertility awareness (natural family planning)

7-minute read

Key facts

  • Fertility awareness (also known as natural family planning) helps identify the days during your menstrual cycle that you are most fertile and can get pregnant.
  • Fertility awareness can be used as a method to avoid pregnancy (contraception), or to try and conceive.
  • There are different ways to practice fertility awareness, including the symptothermal method, ovulation method, calendar method, cervical mucus or Billings method.
  • Fertility awareness is not recommended if you recently stopped hormonal birth control, have irregular periods or are nearing menopause.

What is fertility awareness?

Fertility awareness (also known as natural family planning) helps you to identify which days during your menstrual cycle you are fertile and can possibly get pregnant. It can be used as a form of contraception or to increase your chances of conception.

After ejaculation, sperm can live in the body for up to 5 days. After ovulation, the egg released survives for only 12 – 24 hours. Therefore, you are most likely to conceive on the 5 days preceding ovulation, and the day of ovulation itself.

Your body temperature and cervical mucus change throughout the menstrual cycle. Monitoring these changes can help you identify when you are nearing ovulation . Avoiding sex on the days that you are most fertile reduce your chance of becoming pregnant. Having sex on these days maximises your chance of conceiving.

There are a few methods you can use to practice fertility awareness:

Fertility awareness only works as a method of contraception if you and your partner agree to follow the instructions very carefully. Since you can get pregnant for a few days before and after you ovulate, you need to be very careful not to have sex on these days.

Is fertility awareness suitable for anyone?

Fertility awareness is not suitable if:

What are the advantages of using fertility awareness as contraception?

The advantages of using fertility awareness as contraception include:

What are the disadvantages of using fertility awareness a contraception?

Here are some disadvantages of using fertility awareness as contraception:

What are the types of fertility awareness?

There are different ways to use fertility awareness to avoid pregnancy:

Cervical mucus method or Billings method

Your cervical mucus changes throughout your menstrual cycle. There are 3 distinct consistencies of mucus during your cycle:

  1. Right after your period — your vaginal opening may feel dry, and the mucus may feel flaky and/or sticky.
  2. Around the time of your ovulation — the mucus's texture is like raw egg whites and may become clear, more watery and elastic.
  3. After you ovulate — the mucus becomes cloudy, thicker and sticky.

You can use the changes in your cervical mucus to identify when you are ovulating. You are recommended to avoid sexual intercourse until after you have had 3 consecutive 'dry' days.

Being sexually aroused or having semen in your vagina can make it hard to identify the consistency of your cervical mucus.

This method isn't suitable if you have abnormal bleeding from your vagina or inflammation in your cervix or vagina. It can also be affected by certain medicines which can change your cervical mucus.

Temperature method

Your resting body temperature rises slightly by 0.2 – 0.5°C after you ovulate, and remains elevated until your next period.

This method involves measuring your temperature with a thermometer at the same time every day, immediately after waking up and before you get out of bed. You must measure your temperature in the same location (vagina, rectum or mouth) each time.

Your fertile window ends when your temperature has risen for 3 days in a row.

This method isn't very accurate because many other factors can affect your body temperature including:

It also means you may need to abstain from sex for many days in the month.

Symptothermal method

This method combines 2 or more signs of fertility such as measuring your body temperature and keeping track of your mucus secretions to calculate your fertile days in your cycle.

Combining different methods of fertility awareness makes it more likely to be effective at preventing pregnancy.

Calendar or rhythm method

This method involves calculating your fertile days based on your fertile days in previous months. While this method can be easier to use than monitoring your body for signs of ovulation, it can be quite unreliable. It's also not suitable for people who have irregular periods.

You can find more information about how to use calendar-based methods at Family Planning NSW.

Resources and support

Speak to a maternal child health nurse

Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available 7am to midnight (AET), 7 days a week.

Check your symptoms Find a health service

Healthdirect 24hr 7 days a week hotline

24 hour health advice and information you can count on

1800 022 222

Government Accredited with over 140 information partners

We are a government-funded service, providing quality, approved health information