What is the progestogen-only pill?
The progestogen-only pill is a pill taken to prevent pregnancy. The progestogen-only pill contains one hormone – progestogen. It does not contain any oestrogen.
How does it work?
Progestogen-only pills work mainly by thickening the mucus in the cervix so sperm can’t travel through it. They also change the lining of the uterus so it is less likely to accept a fertilised egg.
Cerazette also works by stopping the production of a monthly egg.
How well does it work?
Typically the progestogen-only pill is 92% effective, which means a pregnancy rate of eight people per 100 each year.
When pills are taken perfectly – meaning no pills are missed – it can be more than 99% effective in preventing pregnancy.
When do I take it?
Some progestogen-only pills must be taken within three hours of the same time every day.
Cerazette must be taken within 12 hours of the same time every day.
What will I notice?
Your bleeding pattern may change. You may have regular periods, irregular or more frequent episodes of bleeding or no bleeding.
Will I still be able to becomE pregnant after I stop taking the progetogen-only pill?
Your natural fertility will return as soon as you stop taking the progestogen-only pill. If you get pregnant while taking the pill, and decide to continue with your pregnancy, the chance of having an abnormal baby is not increased.
Who can use it?
This pill is especially recommended if you are breastfeeding and if you cannot use the combined oral contraceptive pill for medical reasons.
Who should not use it?
This pill is not recommended if you have had breast cancer or if you are taking some medications, over-the-counter preparations or herbal remedies – check with your nurse or doctor if you take regular medicine.
What are the advantages?
- Easy to use – it is simple and convenient.
- Doesn’t interfere with sexual intercourse.
- Does not affect breastfeeding.
- Can be used by people of any age.
- There are very few side effects. Research does not show that the progestogen-only pill causes weight gain, depression or headaches.
What are the disadvantages?
- The pill must be taken every day whether you have sexual intercourse on that day or not. Some progestogen-only pills need to be taken at the same time every day.
- This pill may change your periods. You may have some irregular bleeding for a few months after starting the pill. This does not mean the pill is less effective as long as you have not missed pills. If the bleeding continues, keep taking your pill but check with a nurse or doctor at one of our clinics.
Does this pill protect you from sexually transmissible infections (STIs)?
No. You need to use condoms (and lubricant) as well to protect against STIs.
Does this pill cause cancer?
The research shows no link between the progestogen-only pill and cancer.
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