The progestogen-only pill

A woman can get pregnant if a man’s sperm reaches one of her eggs (ova). Contraception tries to stop this happening by keeping the egg and sperm apart or by stopping egg production. One method of contraception is the progestogen-only pill (POP).

It contains the hormone progestogen but doesn't contain oestrogen. The progestogen-only pill has to be taken every day within a specific three-hour time frame.

How does it work?

The POP thickens the mucus in the cervix, which stops sperm reaching an egg. It also thins the lining of the womb so that an egg can't implant itself there. In some women, it stops ovulation.

How effective is the progestogen-only pill?

If taken correctly, it can be 99% effective. This means that one woman in 100 who use the POP will get pregnant in one year.

Added benefits?

• The POP can be used by women who can't use contraception that contains oestrogen, e.g. because of high blood pressure, previous blood clots or being overweight.
• You can take the POP if you're over 35 and you smoke.

What else should I know?

• You must take the progestogen-only pill at the same time each day: if you take it more than three hours late (or 12 hours late if you take Cerazette) it may not be effective.
• If you’re sick (vomit) or have severe diarrhoea, the POP may not work.
• Some medicines may affect the POP's effectiveness: ask your doctor for details.
• Your periods may stop or become lighter, irregular or more frequent.
• Side effects may include spotty skin and breast tenderness. These should clear up within a few months.

By using condoms as well as the POP, you'll help to protect yourself against sexually transmitted infections (STIs).

Further information

Find out about the 15 methods of contraception

What should I do if I miss a pill (POP)?

What if I'm on the pill and I'm sick or have diarrhoea?

Does the contraceptive pill interact with other medicines?