Combined pill (COC)

Combined pill COCThe combined pill (also known as ‘the pill’), is a small round tablet that releases artificial versions of the oestrogen and progesterone hormones. It has to be taken daily. Almost half of all women using contraception take oral contraceptive pills as their primary method of contraception. The combined pill is most popular amongst women aged between 16 and 24.

The combined pill stops ovulation, which means the woman does not release an egg for fertilisation. It also thickens the mucus around the cervix making it difficult for sperm to get into the womb and thins the womb lining.
There are different types of combined pill, which use different brand names. The most common are 21-day pills, where you take one pill every day for 21 days, then stop for 7 days (to follow your 28-day menstrual cycle). Another option is to take ‘every day’ pills – you take one pill every day with no break, but 7 of these are ‘dummy’ pills which do not contain any hormone.

The combined pill is not always suitable for women who smoke (or stopped smoking less than a year ago) and are 35 or older or those that are very overweight. In this case, the progestogen-only pill (mini pill) could be a better option.



Lasts for


Effect on period


Side effects



  • It does not interrupt sex
  • Usually makes periods regular, lighter and less painful
  • May help with premenstrual symptoms
  • Reduces the risk of cancer of the ovary, uterus and colon
  • Improves acne in some women
  • Can improve symptoms of Pre-Menstrual Syndrome (PMS)
  • When you stop using the pill your fertility will return to normal.


  • It can cause temporary side effects at first, such as headaches, nausea, breast tenderness and mood swings – if these do not go after a few months, it may help to change to a different pill
  • Other side effects can include loss of libido (sex drive) and changes to skin
  • It can increase your blood pressure
  • It does not protect you against sexually transmitted infections
  • Breakthrough bleeding and spotting is common in the first few months of using the pill
  • It has been linked to an increased risk of some serious health conditions, such as thrombosis (blood clots) and breast cancer

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 combined pill will get pregnant each year. It is less effective if it is not taken according to the instructions. With typical use, the combined pill is 91% effective.

What makes it less effective?

  • Not taking it properly.
  • Taking it more than 24 hours late.
  • Vomiting less than 2 hours after taking it.
  • Very severe diarrhoea.
  • Some medicines (including those used to treat epilepsy, HIV and TB, and the herbal medicine St John’s Wort).

What if I miss a pill?

If you have missed one pill, anywhere in the pack:

  • Take the last pill you missed now, and take the next pill at the normal time
  • Continue taking the rest of the pack as usual
  • You don’t need to use additional contraception, such as condoms
  • Take your 7-day pill-free break as normal.

If you have missed two or more pills (you are taking your pill more than 48 hours late) anywhere in the pack:

  • Take the last pill you missed now, even if it means taking two pills in one day
  • Leave any earlier missed pills
  • Continue taking the rest of the pack as usual and use an extra method of contraception for the next 7 days
  • Check how many pills you have left in your pack. If it is more than 7 pills then complete the pack as usual and take the 7-day break at the end of the packet. If you have less than 7 pills left in the pack then miss the break at the end of this packet and start the new packet immediately without the 7-day pill free interval
  • You may need emergency contraception if you have had unprotected sex since missing the pills or in the 7 days before missing the pills
  • If you are not sure what to do, continue to take your pill and use another method of contraception, such as condoms, and seek advice as soon as possible

For more information visit the FPA website.