Progestogen only pill (POP or mini pill)

What it is

Small tablets containing the hormone progestogen.

How it works

Progestogen makes the mucus around the cervix thicker, which makes it difficult for sperm to get into the womb. It can also make it difficult for an egg which has been fertilised to implant in the womb. In some women it stops ovulation (the release of an egg).

Advantages

Does not interrupt sex.

Can be taken by some women who cannot use the combined pill.

Can be used when breastfeeding.

Disadvantages

Does not protect against sexually transmitted infections (STIs).

Periods may be irregular.

How effective is it?

This pill is 99% effective if it is taken properly. This means that 1 in every 100 women who use the progestogen only pill will get pregnant each year. It is less effective if it is not taken according to the instructions.

What makes it less effective?

Not taking it properly.

Taking it more than 3 hours late (or 12 hours if you're taking Cerazette)

Vomiting within two hours of taking it.

Very severe diarrhoea.

Some prescription and complementary medicines (such as St John's Wort).

Can anyone use this method?

The progestogen only pill is not suitable for all women. A doctor or nurse will need to know about a woman's medical history and any illnesses suffered by immediate members of her family, to find out if there are any medical reasons why it might not be suitable.