The progestogen-only pill (POP) is a form of contraception. This page explains the POP and tells you how to use it.
What is the progestogen-only pill (POP)?
The POP is a pill taken to prevent pregnancy. The POP contains one hormone - progestogen. It does not contain any oestrogen.
How does it work?
Some POPs work mainly by thickening the mucus in the cervix so sperm can’t travel through it.
Cerazette also works by stopping the production of a monthly egg, and changes the lining of the womb so it is less likely to accept a fertilised egg.
How well does it work?
Typically the POP is 92% effective, which means a pregnancy rate of eight people per 100 each year.
When pills are taken perfectly i.e. no pills are forgotten, it can be more than 99% effective in preventing pregnancy.
When do I take it?
Some POPs 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. About 40% of those taking this pill have regular bleeding, 40% have irregular bleeding and 20% have no bleeding.
Will I still be able to becoming pregnant after I stop taking the POP?
Your natural fertility will return as soon as you stop taking the POP. 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 POP 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.
- This pill may change your periods. Some irregular bleeding may occur 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 POP and cancer.
Family Planning has clinics located throughout New Zealand. Use the clinic finder to find your nearest clinic.