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Contraception through body observation: Natural family planning explained

When it comes to natural family planning, women need to know their bodies inside out. But what exactly is NFP, what do you need to pay attention to and how can femSense support you?

"I know when I'm fertile and when I'm not by measuring my body temperature and my Cervical mucus observe" - Honestly, when a friend tells you that, it sounds incredible, doesn't it? The whole thing is called natural family planning, or NFP for short, and you can actually use it for contraception. How do you do it? By tracking your body temperature and various body signals. This is called the "symptothermal method" - and femSense can help you with this.

What is NFP?

With natural family planning, you use contraception by observing your body and using the signals your body gives you to determine the time of your pregnancy. Ovulation is estimated. This is because the egg can be fertilised from around 72 hours before ovulation and up to 24 hours after ovulation. In addition, sperm can survive inside you for up to five days, which extends the window of time in which sex can lead to fertilisation. So if you know when you are ovulating, you will also know when there is a high risk of becoming pregnant.

NFP is an umbrella term for various methods of recognising the fertile phase. Women can combine them individually. All methods are based on knowing when you are ovulating. However, all methods have one thing in common: you need to know your body well!

The safety of contraceptives

The different methods of NFP are not all equally safe. The safety of contraceptives is indicated using the Pearl Index. This indicates how many out of 100 women who use a contraceptive method for a year become pregnant. A Pearl Index of 2, for example, means that two out of 100 women are pregnant after one year despite using the contraceptive.

What NFP methods are available?

Temperature method

During ovulation, the body temperature rises by around 0.2-0.5 C°. With the temperature method, you measure your body temperature at the same time every day, directly after waking up - and thus recognise the temperature rise during ovulation. You need a very accurate thermometer for this because the temperature rise is only very slight. In addition, regular sleeping and waking times are a must and you should not have woken up or got out of bed for a few hours before taking your temperature.

Pearl index: approx. 2

Billings method

The Billings method is also known as the cervical mucus method because it involves examining your cervical mucus. Cervical mucus is a secretion secreted by the cervix. In the course of the cycle it changes - The closer you get to ovulation, the clearer and more "spinnable" it becomes. Some women also feel the cervix, as this also gives signs of ovulation; it becomes softer, opens slightly and changes its position in the vagina.

Pearl index: 15

Calendar method

With the calendar method, ovulation is determined purely by calculation. The fertile days are calculated based on the length of the previous cycles. The calendar method is the only contraceptive method that is very unsafe because it is based purely on statistics and not on observing the body.

Pearl index: approx. 20

Symptothermal method

The symptothermal method is the safest version of NFP. It combines the temperature method and the Billings method, i.e. the observation of cervical mucus. With this method, you have double safety because you always have two independent factors that show you whether you are pregnant or not. fruitful or not.

Pearl Index: 0.3

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Is natural family planning for me?

Just take a little temperature and you can't get pregnant - that sounds almost too good to be true. Unfortunately, it's not that simple. You have to be very consistent and, as with all contraceptives, it's not right for every woman. We have summarised 5 points for you that you should know before you decide on natural family planning:

1. self-discipline is a prerequisite

NFP is only safe if you have your Document your cycle in a disciplined manner. You should write down your body signals every day to notice changes immediately. For example, you can use our femSense App perfect. It was specially developed so that women can easily track their cycle. But beware: the femSense app is not a contraceptive!

Apps such as femSense do not replace your personal responsibility when using NFP! They can only support you in documenting your cycle and, above all, in using the Sensor patches increase the safety of contraception. If you are interested in exactly how femSense works, you can find out more here!

2. a regular daily routine is important

Do you work shifts or travel a lot? Then NFP may not be the right method for you. To be able to measure your body temperature reliably, you need to have a relatively regular daily routine without too much stress and sleep problems. The measurement should always be taken at around the same time after a few hours' sleep in the morning. It is important to use a thermometer that is as accurate as possible because the temperature only rises very slightly during ovulation. As accurate as possible means a thermometer with at least two digits after the decimal point.

Instead, however, you can also use the femSense sensor patches use. They have the advantage that you don't have to take your temperature at the same time every day; they measure your temperature automatically and continuously for up to 7 days. You read the data with your smartphone twice a day in a matter of seconds, algorithms analyse it in the background and the app tells you what you need to know: Are you high or low fertile today? Has ovulation been detected?

3. no fear of contact with your own body

You shouldn't be afraid or disgusted by cervical mucus during natural family planning. Over the course of the cycle, cervical mucus changes its consistency and thus indicates ovulation, for example. To notice these changes, you need to check your cervical mucus every day. You can also do this with toilet paper, but the easiest way is to use your fingers.

4. on fertile days with a condom

NFP does not automatically prevent you from getting pregnant, but only helps you to calculate your fertility. On the days when you are fertile, i.e. around ovulation, you must use additional contraception to avoid getting pregnant. For example, you can use a condom or a diaphragm during this phase.

5. more difficult with irregular cycles

It is completely normal for menstrual cycles to vary in length. In 60 per cent of women, the length of their cycle varies by more than a week within a year. However, NFP can become less reliable with very large cycle fluctuations.

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If you used a hormonal contraceptive before NFP, your body may need a few months to recover and return to its natural cycle. You should therefore wait a few months before using natural family planning for contraception.

Are you using hormonal contraception but thinking about stopping? Read on here and find out everything you need to know if you want to stop taking the pill!

Would you like to start tracking your cycle? Why not download our femSense App to start recording your cycle!

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Natural family planning (2023)

Natural family planning (2023)

Pearl Index (2023)

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