The progestogen-only pill (also known as ‘POP’) is a type of contraception containing the hormone progestogen that prevents pregnancy by stopping sperm fertilising an egg.
When used correctly, the progestogen-only pill is 99% effective at preventing pregnancy.
There are two different types of progestogen-only pill: ‘3 hour’ pills must be taken within the same 3 hour period every day. ’12 hour’ pills must be taken within the same 12 hour period.
You will need to take one pill every day. There are 28 pills per pack, and you do not take a break between packs.
The hormone in the progestogen-only pill prevents pregnancy by:
There are two different types of progestogen-only pill:
This pill contains the progestogen hormone levonorgestrel or norethisterone. These must be taken within three hours of the same time each day. It is this type that is referred to as the ‘mini pill’.
Examples are Femulen, Micronor, Norgeston and Noriday.
This pill contains desogestrel (such as Cerazette). This must be taken within 12 hours of the same time each day.
You need to remember to take your pill every day. If you find that you often forget to take your pill, there are long lasting contraception options available.
The pill can become less effective at preventing pregnancy if:
The chance of getting pregnant depends on when the pills are missed, how many pills are missed and whether you have had sex without using another form of contraception such as condoms.
First check your pill packet.
If you are on a pill containing desogestrel then you are taking a 12 hour pill. This means that each pill must be taken within 12 hours of the same time every day.
If you are on a pill containing norethisterone or levonorgestrel, then you are taking a three hour pill. This means that the pill must be taken within three hours of the same time every day.
If you are not sure what to do, continue to take your pill and use another method of contraception, such as condoms, and seek advice from your sexual health clinic or GP as soon as possible.
If you start your pill in the first day of your cycle then it will be effective immediately. If you start your pill at any other time on your cycle then you should use additional protection for 48 hours.
The progestogen-only pill may prevent ovulation and therefore prevent you going through your usual menstrual cycle. It is normal for people's periods to stop or become lighter or irregular. At the beginning this may be worrying, and some people will end up taking a few pregnancy tests before they feel confident that the pill is working.
Get in touch with Brook Blackburn if you’d like to discuss this with one of our clinicians.
Some people find that their weight changes due to fluid retention or an increase in appetite, but this should settle over time.
If you are healthy and there are no medical reasons for you not to take the progestogen-only pill, you can take it until your menopause or until you are 55 years old.
The progestogen-only pill has a different hormone than the combination in the combined pill, so if you have had side effects on the combined pill then you may wish to try the progestogen-only pill as an alternative.
Yes, you can easily change between pills.
Some reports suggest that may may be a very small increased risk of breast cancer and cervical cancer, but the pill does help protect against other types of cancers such as ovarian, colon and uterine cancers.
Yes, you can use the progestogen-only pill after having a baby and while breastfeeding.
Some reports suggest that there may be a very small increased risk of breast cancer and ovarian cancer, but the pill does help protect against other types of cancers such as womb, colon and uterine cancers.
You may sometimes be provided with or prescribed a different brand of pills, but the nurse or clinician will explain that the hormones and doses will be the same. The clinics are likely to stock the pill that was cheaper at the time.
When you stop using the progestogen-only pill your fertility will return to normal. There is no evidence to suggest the pill causes infertility.
Most people who have regular periods will find that their normal cycle will return within six months. Some people find that their usual cycles begin again very quickly after stopping, but for others it can take longer.
When you first start the pill you will usually be given three months' supply to see how it suits you. After that you should go back to the doctor or nurse to get new supplies and to have your blood pressure checked. If there are no problems, you can be given up to a year’s supply of the pill.
Some medicines make the progestogen-only pill less effective (including those used to treat epilepsy, HIV and TB, and the herbal medicine St John’s Wort). Ask your GP, clinician or pharmacist and read the information that comes with your medicine.
The antibiotics rifampicin and rifabutin (which can be used to treat illnesses including tuberculosis and meningitis) can also reduce the effectiveness of the progestogen-only pill. Other antibiotics do not have this effect. If you are prescribed rifampicin or rifabutin, you may need additional contraception (such as condoms) while taking the antibiotic and for 28 days after.
Always tell your doctor that you are taking the progestogen-only pill if you are prescribed any medicines.
You may not be able to take the progestogen-only pill if you have or have had:
Speak to your GP or sexual health clinic about whether the progestogen-only pill is right for you.
If you vomit within two hours of taking the progestogen only pill, it may not have been fully absorbed into your bloodstream.
Take another pill straight away and the next pill at your usual time. If you don’t take the replacement within three hours (or 12 hours for the 12-hour pill) of your normal time, use additional contraception, such as condoms, for two days.
If you continue to be sick, keep using another form of contraception while you're ill and for two days after recovering.
Very severe diarrhoea (6 to 8 watery stools in 24 hours) may also mean that the pill doesn't work properly. Keep taking your pill as normal, but use additional contraception, such as condoms, while you have diarrhoea and for two days after recovering.
Speak to your GP or contraception nurse or call NHS 111 for more information, or if your sickness or diarrhoea continues.