Progesterone-only pill

the pill

The Progesterone-only Pill contains progesterone with no oestrogen. It must be taken consistently at the same time every day to be the most effective.

Like all contraceptive methods other than condoms, the Progesterone-only Pill does not protect against sexually transmitted infections.

There are 2 types of the Progesterone-only Pill, a 3-hour and a 12-hour one. The 3 hour pill must be taken within 3 hours of the same time everyday, and the 12 hour pill must be taken within 12 hours of the same time everyday - leaving more room for mishaps.

Once you finish one pack of pills then you start a new one.

The pill works by preventing the ovaries from releasing an egg, it also:

  • Thickens the mucus in the neck of the womb which prevents sperm getting to the egg
  • Makes the lining of the womb thinner, making it harder for a fertilised egg from implanting itself into the womb

The Progesterone-only Pill is over 99% effective when used correctly*, meaning less than 1 in every 100 women who used the it became pregnant over a 1 year period.

* Some women find it hard to take the pill consistently at the same time every day - making it less effective at preventing pregnancy. There are better options for contraception available such as IUD, IUS, injection and implant.

You should visit your doctors surgery or sexual health clinic and ask about starting to take the Progesterone-only contraceptive pill. You can find your nearest sexual health clinic here.

  • Can take if overweight
  • Can take if you smoke
  • Does not interrupt sex
  • Can be used if breastfeeding
  • Can be used at any age
  • Have to remember to take the pill every day
  • Must take at the same time every day or there is a reduction in its effectiveness
  • Periods can become irregular, lighter or more frequent
  • Some medicines may make the pill less effective
  • Side effects of acne and breast tenderness which usually clear up within 3 months
  • Does not protect against sexually transmitted infections (STIs)