Fertilidad

Fertility awareness methods

Revisado: 4 de octubre de 2026

Solo en inglés por ahora

Fertility awareness means tracking body signs to work out your fertile days. It can work well when learned properly, but with typical use it is much less reliable.

What fertility awareness is

Fertility awareness methods, also called natural family planning, help you work out the days in your cycle when you could get pregnant. You record signs from your body every day. To avoid pregnancy, you then avoid sex or use another method, such as condoms, on your fertile days. Some people use the same skills to time sex when they want a baby.

The signs you track

There are several methods. The temperature method uses your body temperature at rest, which rises slightly just after ovulation. The cervical mucus method follows changes in your vaginal discharge, which becomes clear and slippery around ovulation. The calendar method uses the length of your past cycles. Using all three together, sometimes called the symptothermal method, is more effective than relying on one alone.

How effective it is

Effectiveness depends a lot on how carefully the method is used. The NHS says that with perfect use, fertility awareness is between 91% and 99% effective at preventing pregnancy. With typical use, which allows for the mistakes people make in real life, it is only 76% effective: about 24 in 100 women using it get pregnant in a year.

Learning it properly matters

Fertility awareness takes skill and commitment, and it works best when you learn it from someone trained. The NHS advises learning it from a health professional who is specially trained in fertility awareness. It says it can take 2 to 3 cycles to learn the method properly. You need to record your signs every day. The methods work less well if your cycles are irregular, so they may not suit everyone.

Apps, STIs and other limits

Fertility awareness does not protect you from sexually transmitted infections (STIs), so use condoms as well if you could be at risk. Ciclo logs cervical mucus and ovulation tests but not temperature, and its fertile window is an estimate, not contraception. If you want help choosing a reliable method, talk to a doctor, nurse or sexual-health clinic.

This is general information. Fertility awareness needs proper training to work well and does not protect against STIs. Ask a doctor or nurse about your options.