Natural family planning
NHS Choices - Introduction
Natural family planning is when natural signs, such as body temperature, are used to identify when a woman is at her least and most fertile during each menstrual cycle, to help either avoid or plan pregnancy. This is known as fertility awareness.
There are a number of ways to assess whether it is likely that you are currently fertile. You can:
- calculate where you are in your menstrual cycle (how long since your last period) – most women ovulate (produce an egg that is ready for fertilisation) 10-16 days before they have their period
- check the consistency of the mucus in your cervix (the opening to the womb) –if the mucus looks white and creamy in colour it is normally a sign that you are fertile
- take your temperature daily – if your temperature rises above normal for a few days it is usually a sign that you are no longer fertile
Read more about how natural family planning is performed.
Is it reliable?
In theory natural family planning can be up 99% effective in preventing unwanted pregnancies.
However, in practice natural family planning can be a complex procedure and it’s often possible to make a mistake when assessing fertility.
In reality natural family planning is estimated to be around 75% effective - so 1 in 4 women using this method of birth control may still become pregnant.
The same is also true of other methods of birth control. For example, male condoms are, in theory, 98% effective in preventing unwanted pregnancies, but in reality it’s more like 85% - so around 1 in 7 women using still become pregnant.
Read more about the results of natural family planning when compared to other methods of birth control.
Who can use it
Provided it’s followed correctly (usually with proper instruction from a trained natural family planning teacher) most women can use natural family planning effectively. There may be circumstances in which it is not recommended as a form of birth control, including:
- if you had a serious health condition that could be made worse if you became pregnant, or alternatively could place the life of any baby you had at risk, such as heart disease – a more reliable method of birth control would usually be recommended
- if you had a condition that could disrupt your normal reproductive cycle such as polycystic ovary syndrome or cervical cancer
Natural family planning requires commitment from both members of a couple so it may only be suitable for you if you are currently in a stable relationship.
Read more about who is best suited to using natural family planning.
Pros and cons
Advantages of natural family planning include:
- it does not cause any side effects
once the techniques have been learnt
- there should be no further input from health professionals
- natural family planning is acceptable to all faiths and cultures
Disadvantages of natural family planning include:
- natural family planning does not protect against sexually transmitted infections (STIs) such as chlamydia or HIV
- you will need to abstain from sex during the fertile time of your menstrual cycle which some couples can find difficult
- it is not as effective , as other forms of birth control, such as the contraceptive implant
Read more about the pros and cons of natural family planning.