Emergency contraception can be used to prevent an unintended pregnancy after having unprotected sex or when a contraceptive method has failed (for example, if a condom breaks). In certain circumstances, when using Natural Cycles, you might consider using emergency contraception depending on where you are in your cycle. The fertile window is six days per cycle and consists of the five days before ovulation and the ovulation day, so if you have unprotected sex during this window, you are at risk for pregnancy.
When using NC° Birth Control, you should abstain or use a barrier method, such as condoms, if you have vaginal sex on Red Days. Read more here.
Please consult your healthcare professional if you are unsure about using emergency contraception. This information is provided for educational purposes only and is not intended to replace the advice of your healthcare professional.
What are the options for emergency contraception?
There are two options to choose from: the emergency contraceptive pill or the copper IUD. If you have questions about which option would work best for you, we encourage you to reach out to your healthcare professional, who can help you decide.
How emergency contraceptive methods work
Emergency contraceptive pills contain either levonorgestrel or ulipristal acetate and work by delaying ovulation (2,3). They can be effective if you take them before ovulation happens and as soon as possible after having unprotected sex. Some brands need to be taken within 72 hours, and others within 120 hours.
The copper IUD works by stopping the implantation of a fertilized egg, and it can be used at any point during the fertile window and for a few days after ovulation has occurred. It is the most effective emergency contraceptive method. (1)
Using the Natural Cycles app to understand where you are in your cycle can help you and your healthcare professional decide which method would be best for you. In the Graph view, you can see whether or not your ovulation has been confirmed and where you are in relation to your ovulation day.
Keep in mind that emergency contraception is different from mifepristone (RU-486 or 'abortion pills'), which acts to terminate an established pregnancy where implantation of a fertilized embryo has occurred. There is also another kind of pill, called Period Pills, that can be used to start your period if it is late and you suspect that you may be pregnant.
How should I use the app after I’ve used emergency contraception?
You should log that you have used emergency contraception in the app. To do this, open the Add data page for the day that you used an emergency contraceptive method and scroll down to Emergency contraception & Tests > select either Pill or IUD.
Once you have logged emergency contraception in the app, we recommend that you continue adding your temperature each day as usual. You will be able to see on which day you logged emergency contraception in your Graph view – the pill or IUD symbol will be shown above the day you took it.
If you have taken the emergency contraceptive pill, the Natural Cycles algorithm will take into account that the hormones in the pill will affect your temperatures, so you can expect a few more Red Days in the cycle that you’ve taken it. The copper IUD is non-hormonal, so your temperature won't be affected by it.
It is also very important that you continue to abstain from sex or use barrier protection (we recommend condoms) on all your Red Days.
You may experience some spotting or bleeding soon after using emergency contraception – this is not your period, and you should log it as Spotting in the app. If you are not sure which type of bleeding you are experiencing, please reach out to your healthcare professional.
It is common for the cycle in which you’ve used emergency contraception to be slightly different (either longer or shorter) than it usually is for you. However, if your period is more than one week late, you should take a pregnancy test. The algorithm can also detect a possible pregnancy if your data indicates so, and it will then prompt you to take a test. We write a bit more about this here.
If you would like to learn more about emergency contraception and how it works, we have a blog post about it here.
- Cleland K, Zhu H, Goldstruck N, Cheng L, Trussell J. The efficacy of IUDs for emergency contraception: a systematic review of 35 years of experience. Hum Reprod. 2012;27:1994–2000.
- Glasier AF, Cameron ST, Fine PM, Logan SJ, Casale W, Van Horn J, Sogor L, Blithe DL, Scherrer B, Mathe H, Jaspart A, Ulmann A, Gainer E. Ulipristal acetate versus levonorgestrel for emergency contraception: a randomised non-inferiority trial and meta-analysis. Lancet. 2010;375:555–62.
- Richardson AR, Maltz FN. Ulipristal acetate: review of the efficacy and safety of a newly approved agent for emergency contraception. Clinical therapeutics. 2012 Jan 31;34(1):24–36.