Natural family planning (fertility awareness)

Natural family planning is checking and recording fertility signs to work out when you’re more likely to get pregnant. It’s sometimes called fertility awareness. You can then avoid having sex, or use other contraception when you’re more likely to get pregnant.

Natural family planning is much less effective than other methods of contraception. It requires mutual agreement, self-control and dedication. It does not protect you against sexually transmitted infections (STIs).

If the instructions are properly followed, natural family planning methods can be up to 99% effective, depending on what methods are used. This means that 1 in 100 people who uses natural family planning will get pregnant in a year.

It’ll be less effective if it’s not used according to the instructions. It may only be around 75% effective because of mistakes.

Natural family planning does not cause any side effects. It’s acceptable to all faiths and cultures.

How natural family planning works

Natural family planning can take up to 6 months to learn.

Fertility signs indicate when you can have sex with a lower risk of pregnancy.

You need to check your fertility signs every day.

Fertility signs

Natural family planning is more likely to work if you check all your fertility signs.

You can use fertility charts or apps to record information. You can then track over the course of each menstrual cycle.

Although fertility apps allow you to check your fertility signs and estimate your most fertile time period, they are not completely reliable.

Body temperature

There’s a small rise in body temperature after you release an egg (ovulation).

To measure your body temperature, you’ll need either:

a digital thermometer
a thermometer specifically designed for natural family planning

These are available from pharmacies. Ear or forehead thermometers are not accurate enough to be used in this way.

You take your temperature every morning before you get out of bed. This should be done:

before eating or drinking anything
before smoking
at the same time every morning

You check for 3 days in a row when your temperature is higher than all of the previous 6 days. The increase in temperature is very small, usually around 0.2°C (0.4°F). It’s likely that you’re no longer fertile at this time.

Changes to your cervix

There’s a change in the amount and consistency of discharge from your cervix during your menstrual cycle. You can also notice that the cervix feels a bit higher or lower in the vagina at different times of the cycle.

You can check this by gently placing your middle finger into your vagina and pushing it up to around your middle knuckle. For the first few days after your period, you’ll probably find that your vagina is dry and you cannot feel any mucus.

As the levels of hormones rise to prepare your body for ovulation, you’ll probably find that your cervix is now producing mucus that is:

moist and sticky
white and creamy

This is the start of the fertile period of your menstrual cycle. Immediately before ovulation, the mucus will get:

wetter
clearer
slippery, a bit like raw egg white

This is when you’re at your most fertile.

The mucus should then soon return to being thicker and sticky. After 3 days you should no longer be fertile.

Your menstrual cycle

The length of your menstrual cycle can indicate when you’re fertile.

You need to take into account that:

you cannot predict exactly when you’ll release an egg (ovulation)
your menstrual cycle can vary over time so you’ll need to measure it over 12 months to be as precise as possible
it’s not reliable and should not be used on its own as a fertility signal

Learn about how your periods are linked to fertility and pregnancy

Who can use natural family planning?

Most women are able to use natural family planning.

It may not be right for you if:

you’re dependent on drugs or alcohol, or take medications known to cause birth defects
you’re having irregular periods, so predicting your fertile time may be hard or impossible
you have an infection or imbalance that changes your fertility signs, such as pelvic inflammatory disease (PID), a sexually transmitted infection (STI) or bacterial vaginosis
you have a long-term condition that changes your fertility signs, such as liver disease, an over or underactive thyroid gland, cervical cancer or polycystic ovary syndrome (PCOS)
you’re taking a medication that changes cervical mucus such as lithium (used to treat serious mental health conditions like bipolar disorder) and some older types of antidepressants
you have an increased risk of catching an STI – for example, you have multiple sexual partners

Things that affect your fertility signs

Things that can change your normal fertility signs and make natural family planning unreliable are:

irregular periods
if you’ve recently stopped taking hormonal contraception
if you’ve recently had a miscarriage or an abortion
if you’ve recently given birth and are breastfeeding
regular travel through different time zones
vaginal infection such as thrush or an STI
changing how and when you take your temperature
drinking alcohol
taking certain medication
illness
some long-term conditions
stress

the emergency contraceptive pill – if you use this you’ll need to wait for 2 full cycles before relying on natural family planning again

Breastfeeding as a contraceptive

Breastfeeding can be used as a method of contraception until a baby is 6 months old. This is known as the Lactational Amenorrhoea Method (LAM). If followed correctly it’s 98% effective.

The fertility signs used in natural family planning methods are not reliable in women who are breastfeeding.

Withdrawal (pulling out, ‘being careful’ Coitus interruptus)

Taking the penis out of the vagina before ejaculation is 80% effective as a method of contraception. However, sperm can come out of the penis before full ejaculation (come). This can lead to pregnancy.

Where you can get contraception?

You can get contraception from:

sexual health services
GP practices that provide contraception
some pharmacies

Natural family planning advice or support is not routinely provided by the NHS.

If you’re under 16

Anyone can get contraception for free in Scotland, even if you’re under 16.

Contraception services are confidential so the person won’t tell anyone else about it. You can ask them any questions you may have.

If you’re under 16, they might encourage you to tell your parents, but you do not have to.

The only time a professional might need to tell someone else is if they think you’re at risk of harm, such as abuse. The risk would need to be serious. They’d usually talk about it with you first.