Natural family planning This is a method of preventing or planning a pregnancy that doesn't involve any pills or devices, and has the added bonus of getting you more in touch with your body, as this fpa factsheet explains.

In this article

What is it?

How do you use it?

Can anyone use NFP?

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

How reliable is it?

Its effectiveness depends on how carefully it's used. If used according to teaching and instructions it is over 98 per cent effective. This means that using this method as contraception, fewer than two women in 100 will become pregnant in a year.

It's most effective when taught by a specialist NFP teacher and when more than one fertility indicator is used.

Myth: Natural family planning isn't effective
Fact: Not true - NFP is highly effective when used correctly
Myth: Natural family planning is difficult to use
Fact: Not true - NFP is easy to use once you have been taught correctly and have good support

There are also a number of different fertility devices that work by monitoring changes in temperature, urine or saliva. In the UK, the main product is called Persona. This is about 94 per cent effective. This means, using this method, at least six women in 100 will become pregnant in a year.

NFP works by observing and recording your body’s different natural signs or fertility indicators on each day of your menstrual cycle. The main fertility indicators are:

• Recording your body temperature - your body temperature changes through the menstrual cycle under the influence of estrogen and progesterone. It rises slightly after ovulation. Charting these changes each day will show when ovulation has occurred.
• Monitoring cervical secretions (cervical mucus) - the amount of estrogen and progesterone varies during the menstrual cycle, which alters the quantity, texture and appearance of cervical mucus, seen as vaginal secretions. Charting these changes can help you identify the start and end of your fertile time
• Calculating how long your menstrual cycle lasts - charting how short or long your menstrual cycles are over six months can give you an idea of your cycle length.

Combining these different fertility indicators acts as a double-check and increases the effectiveness of NFP.

Advantages:

• Makes you more aware of your fertility and helps you plan or prevent pregnancy
• Doesn't involve any hormones or devices
• No physical side-effects
• Acceptable to all faiths and cultures
• Can help recognise normal and abnormal vaginal secretions

Disadvantages:

• It takes time to learn to use the method
• You have to keep daily records
• Some events such as travel, illness, lifestyle or stress can make fertility indicators harder to interpret

Most women can as long as they receive good instruction and support. It can be used at all stages of your reproductive life, whatever age you are.

It may take longer to recognise your fertility indicators and to start to use NFP if you have irregular menstrual cycles, or at certain times - for example, after stopping hormonal contraception, after having a baby or when approaching the menopause.

Other things to consider

Natural family planning does not protect you against sexually transmitted infections.

Advice and support

You can ask about NFP at your contraception clinic, sexual health clinic or GP surgery.

Call fpa's helpline on 0845 122 8690.

This article was last reviewed in July 2007.