What is the progestogen-only pill?
The progestogen-only pill is used to prevent pregnancy. It’s made from only one hormone (progestogen). Every pill in the packet is the same. It has also been known as the mini pill.
How does the progestogen-only pill work?
The progestogen-only pill works by:
- making the mucus (sticky fluid) at the opening of the uterus thicker so sperm can’t get through
- changing the lining of the uterus so a fertilised egg can’t take hold
- sometimes stopping the release of an egg by the ovary (ovulation)
How effective is the progestogen-only pill?
If taken correctly, it is 92-99% effective.
What's good about the progestogen-only pill?
The progestogen-only pill:
- can be safely used during breastfeeding as it does not interfere with the milk supply
- is less likely to cause nausea (feeling sick) and headaches than the combined Pill
- can be used by women who cannot take oestrogen, which is the other hormone found in the combined Pill
What are the side effects?
It is likely that there will be changes to your periods, such as spotting, irregular periods or heavy periods. Sometimes periods may stop altogether.
If you have breakthrough bleeding (vaginal bleeding at times other than your period) while taking the progestogen-only pill, don’t stop, continue the packet as usual. This is common, but consult a doctor if it persists or troubles you.
Other side effects can include headaches, breast tenderness and nausea. These will often decrease or stop after the first month.
When does it start working?
It’s immediately effective if started during the first 5 days of your menstrual cycle, which starts with the first day of bleeding.
The progestogen-only pill is effective after 2 days (48 hours) if it is started at any other time in the menstrual cycle. Other contraceptive measures such as condoms should be used for these 2 days.
If changing from the Pill or another method of contraception, or after having a baby, discuss the best time for starting with your doctor.
How do I take it?
- Take the progestogen-only pill every day.
- There are no sugar pills to take, or a 7-day break as with some combined pills.
- It’s important to take the progestogen-only pill at the same time every day for maximum effectiveness. Choose a time when you are most likely to remember taking it, and keep to it. If you are more than 3 hours late you will not be protected.
- You could use your mobile as a daily reminder/alarm.
What can stop the progestogen-only pill from working?
Vomiting or diarrhoea
The progestogen-only pill may not work if vomiting occurs within 2 hours of taking a pill. Very severe diarrhoea can also sometimes interfere with it. If you have vomiting or diarrhoea, keep taking the progestogen-only pill, but remember that you might not be protected. Use another method of contraception (e.g. a condom) until you have been able to take the progestogen-only pill for 48 hours.
A missed pill
If you forget to take a pill, or are more than 3 hours late, take it as soon as you remember and take the next pill at the usual time. Continue normal pill taking and use another method of contraception (e.g. a condom) for the next 48 hours.
Some medication and non-prescribed medication (e.g. St John’s Wort) may interfere with the progestogen-only pill. Discuss with your doctor any medications you are taking.
For women who are breastfeeding
The progestogen-only pill can be started shortly after the birth of your baby, often before leaving hospital. Research has shown that the amount of hormone that might pass through the breast milk is extremely low, and will not harm the baby.