Contraception - progestogen-only pill - your guide (fpa)

This information is from the Family Planning Association (fpa). For more information, see the fpa website at www.fpa.org.uk.

This pill contains a progestogen hormone which is similar to the natural progesterone women produce in their ovaries. Progestogen-only pills are different to combined pills because they do not contain any estrogen. There are different types of POP available, some containing different progestogens.

The POP works in a number of ways.

• It mainly works by thickening the mucus from your cervix. This makes it difficult for sperm to move through it and reach an egg.
• It makes the lining of your uterus (womb) thinner so it is less likely to accept a fertilised egg.
• It sometimes stops your ovaries releasing an egg (ovulation). This is the main action of one POP, Cerazette. This may mean that Cerazette is more effective than other POPs, but research has not yet confirmed this.

You can go to a contraception or sexual health clinic, or general practice. If you prefer not to go to your own general practice, or if they don’t provide contraceptive services, they can give you information about another practice or clinic. All treatment is free and confidential. You don’t need to have a vaginal or breast examination or cervical screening test when you are first prescribed the POP. See Where can I get more information and advice?.

Not everyone can use the POP and a doctor or nurse will ask you about your own and your family's medical history. Do mention any illness or operations you have had. Some of the conditions which may mean you should not use the POP are:

• you think you might already be pregnant
• you take certain medicines.

You have now or have had in the past:

• heart disease or a stroke
• active disease of the liver
• current breast cancer or breast cancer within the last five years
• migraines with aura.

If you are healthy and there are no medical reasons for you not to take the POP you can take it until your menopause or until you are 55 years.

Some of the advantages of the POP are:

• it doesn't interfere with sex
• you can use it if you are breastfeeding
• it is useful if you cannot take estrogens, like those found in the combined pill, contraceptive patch or contraceptive vaginal ring
• you can use it at any age, but it is especially useful if you smoke and are 35 or over
• it may help with premenstrual symptoms and painful periods.

There are no serious side effects with the POP. However:

• You may not have regular periods while you are taking the POP. Your periods may be irregular, light, or more frequent or may stop altogether. This may settle down and is not harmful but you may find it annoying. If you have any concerns see your doctor or nurse. Changing to a different POP may help.
• The POP does not protect you against sexually transmitted infections, so you may need to use condoms as well.
• You have to remember to take the pill at the same time every day.
• You may get some temporary side effects when you first starting taking the POP, these should stop within a few months. They include spotty skin, breast tenderness, weight change and headaches.

The POP is a very safe pill to take but there are some risks.

• Some women may develop small fluid-filled cysts on their ovaries. These are not dangerous and do not usually need to be removed. Often there are no symptoms, but some women may have pelvic pain. These cysts usually disappear without treatment.
• If you do become pregnant while you are taking the POP there is a small increased risk of you having an ectopic pregnancy. An ectopic pregnancy develops outside your uterus, usually in a fallopian tube. Although this is not common, it is dangerous. This risk of ectopic pregnancy is less in women using the POP than in women using no contraception at all.
• Research about the risk of breast cancer, cervical cancer and hormonal contraception is complex and contradictory. Research suggests that users of all hormonal contraception appear to have a small increase in risk of being diagnosed with breast cancer compared to non-users of hormonal contraception. Further research is ongoing.

You can start the POP anytime in your menstrual cycle if you are sure you are not pregnant.

If you start the POP on the first day of your period you will be protected against pregnancy immediately.

You can also start the POP up to and including the fifth day of your period and you will be protected from pregnancy immediately. However, if you have a short menstrual cycle with your period coming every 23 days or less, starting the POP as late as the fifth day of your period may not provide you with immediate contraceptive protection. This is because you may release an egg (ovulate) early in your menstrual cycle. You may wish to talk to your doctor or nurse about this and whether you need to use an additional contraceptive method for the first two days.

If you start the POP at any other time in your menstrual cycle you will need to use another contraceptive method for the first two days of your pill taking.

You can start taking the POP immediately after a miscarriage or abortion if you were pregnant for less than 24 weeks. You will be protected from pregnancy straightaway.

When taking your first pill choose a convenient time to take it. This can be anytime of the day.

Once you have chosen a time you must then take one POP each day at this same time until you finish all the pills in the pack.

You then start a new pack the next day so there are no breaks between packs.

For your pill to work it is important not to take it more than three hours (12 hours for Cerazette) after your chosen time. If you remember later than this, don't panic – see What do I do if I forget a pill?.

If you are changing to another POP or from the combined pill you may be advised to start the new pill immediately or start the day after you take your last pill. Do not have a break between packs. There is no need to wait for your period. You will then continue to have protection from pregnancy.

If you are late in taking your pill or you miss one or more pills (see What do I do if I forget a pill?).

• If you vomit within two hours of taking the pill or if you have very severe diarrhoea. If this happens continue taking the pill as usual and use an extra method of contraception, such as condoms, during the stomach upset and for two days after.
• If you are given medicines by a doctor, nurse or hospital always say that you are taking the POP. Commonly used antibiotics do not affect the POP. Medicines such as some of those used to treat epilepsy, HIV and TB and the complementary medicine St John’s Wort may make it less effective. These are types of drugs called enzyme inducers. If you take these medicines, talk to your doctor or nurse about how to take the POP or whether you need to use a different method of contraception.
• If you are worried about the POP not working and you are not sure what to do, seek advice straightaway. Until you do, use an extra contraceptive method, such as condoms, when you have sex.

If you are more than three hours late (12 hours if you are taking the POP, Cerazette):

• Take a pill as soon as you remember. If you have missed more than one pill only take one.
• Take your next pill at the usual time. This may mean taking two pills in one day. This is not harmful.
• Your are not protected against pregnancy. Continue to take your pills as usual, but use an extra method of contraception, such as condoms, for the next two days.

If you are less than three hours late (12 hours if you are taking the POP, Cerazette):

• Take a pill as soon as you remember, and take the next one at the usual time. You are protected from pregnancy.

If you took all your pills correctly and you didn't have an upset stomach or take any other medicines which might affect the POP, then it is unlikely you are pregnant. Continue to take your pills as normal. There is no evidence that if you take the POP when you are pregnant it will harm the baby. If you are worried ask your doctor or nurse for advice or do a pregnancy test. Taking the POP does not affect a pregnancy test.

You should seek medical advice as soon as possible if you have a sudden or unusual pain in your lower abdomen or if your period is shorter or lighter than usual. These might be the warning signs of an ectopic pregnancy.

When you first start the POP 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 one year’s supply of pills.

If you have no medical problems you can take the POP until your menopause.

Yes. The POP can be started any time after the birth. If you start the POP after day 21 you will need to use additional contraception for two days. You can breastfeed while you are taking the POP. A tiny amount of hormone enters your breast milk, but research has shown this will not harm your baby.

You can try to get pregnant as soon as you stop taking the POP. You can stop taking the pill at any time. Ideally you should wait for one natural period before trying to get pregnant, so you will need to use another method of contraception, such as condoms. This means the pregnancy can be dated more accurately and you can start pre-pregnancy care such as taking folic acid and stopping smoking. You can ask your doctor or nurse for advice. Don't worry if you get pregnant sooner, it will not harm the baby.

If you have had sex without using contraception or think your method might have failed there are two emergency methods you can use.

• The emergency hormonal pill – must be taken up to three days (72 hours) after sex. It is more effective, the earlier it is taken after sex.
• An IUD – must be fitted up to five days after sex, or up to five days after the earliest time you could have released an egg (ovulation).

Ask your doctor or nurse about getting emergency pills in advance, just in case you need them.

Most methods of contraception do not protect you from sexually transmitted infections.

Male and female condoms, when used correctly and consistently, can help protect against sexually transmitted infections. Diaphragms and caps may also protect against some sexually transmitted infections. If you can, avoid using condoms containing Nonoxinol 9 (spermicidally lubricated), as this does not protect against HIV and may even increase the risk of infection.

Find out where to get more information and advice.