What is the progestogen-only pill?
The progestogen-only pill contains the hormone progestogen. The pill is taken orally at the same time each day, following specific instructions. It works by thickening the mucus from the cervix. This makes it difficult for sperm to move and reach an egg cell. It also makes the lining of the uterus thinner and less likely to accept a fertilised egg cell. In some women, it prevents ovulation.
If used according to the instructions, the progestogen-only pill is 99% effective.
What are the advantages?
- Useful for older women who smoke and women who cannot use the combined pill
- Can be used when breast feeding
What are the disadvantages?
- Periods may be irregular, with some bleeding in between or missed periods
- May be less effective in women who weigh over 70kg (11 stone)
- If women are sick, or have severe diarrhoea within three hours of taking the pill, they will need to use an extra contraceptive method (e.g. condoms) over the next seven days