This website has been developed and fully funded by Bayer plc for a UK audience only. Disclaimer and side effect reporting information can be found at the bottom of the page.

Natural family planning

Natural family planning


Other names: fertility awareness; rhythm method


what is natural family planning?

Natural family planning involves being able to identify the signs and symptoms of fertility during the menstrual cycle so you can plan or avoid pregnancy.

family planning


Natural family planning is a type of natural method


Natural family planning belongs to a group of methods called natural methods. Natural methods of contraception include natural family planning, the lactational amenorrhoea method and the withdrawal (pull out) method. They are natural because they do not involve hormones, chemicals or manmade substances.

How does Natural family planning work?

Natural family planning prevents pregnancy by calculating your 'fertile window' and avoiding sex or using barrier methods such as condoms on those days. The ‘fertile window’ is the day an egg is released from the ovary (ovulation) and the five days beforehand. Having sex (intercourse) during this time gives you the best chance of getting pregnant.


By only having unprotected sex on days outside of the fertile window it reduces the likelihood of an egg being fertilised. It’s important to remember that it's not an exact science and can take several months to learn effectively.


There are 3 different fertility signals you can monitor and record for natural family planning. These are:


The length of your menstrual cycle.


Daily readings of your body temperature.


Changes to your cervical secretions (cervical mucus).

It's best to record these measures together to give you a more accurate picture of when you're likely to be most fertile.

How effective Natural family planning?

Typically, natural family planning is 76% effective at preventing pregnancy but can be more than 95% effective if done perfectly. Using a combination of natural family planning methods and using another method of contraception like a barrier method during your most fertile days makes this method more effective.





women icon

Approximately 5 out of every 100 women in a year will experience an unintended pregnancy.




women icon

Approximately 24 out of every 100 women in a year will experience an unintended pregnancy.

    No. Natural family planning is hormone-free.

    Natural family planning is a common choice for those who don't wish to use chemical or hormonal contraceptives, and if you do decide to get pregnant in the future, all that fertility tracking can be a great help.


    Most women can use natural family planning. However, certain situations can affect fertility signs and you might want to consider a different method if:


    • There could be a health risk to the baby if you got pregnant or if it is very important to you not to get pregnant right now.


    • You're having irregular periods (this can make it difficult to track where you are in your cycle).


    • You have a sexually transmitted infection (STI) or pelvic inflammatory disease (these can affect your fertility signs).


    • You're taking a medication that disrupts production of cervical mucus (ask your GP or a pharmacist if you're not sure).


    • You've recently stopped taking hormonal contraception.


    • You've recently had a miscarriage or abortion.


    • You've recently given birth and are breastfeeding.


    • You regularly travel through different time zones.


    • You have a vaginal infection such as thrush.


    • You're not able to take your temperature in the recommended way.


    • You're a heavy drinker.

    GP visit

    Talking to your doctor

    Get the information you need for an informed discussion with your doctor.


    Learn more

    PP-UN-WHC-GB-0084 September 2023


    The health information on this site has been reviewed and approved by Bayer by an appropriately qualified medical reviewer. It is intended as general information only. It is not intended to replace a consultation with a healthcare professional, to provide specific medical advice or replace the patient information leaflet provided with your medicine. Treatments discussed here should be initiated under medical supervision. For full information including side effects and eligibility for treatment, please consult your healthcare professional. Always speak to your doctor or nurse for personal medical advice.


    Images on this site are stock images and for illustrative purposes only.


    Reporting side effects

    If you get any side effects whilst taking a medicine, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also report side effects directly via the yellow card scheme at By reporting side effects, you can help provide more information on the safety of medicines.