The combined pill The combined pill is one of the most popular forms of contraception. This fpa factsheet will help you decide if it's right for you.

In this article

What is it? How does it work?

How reliable is it? Can anyone use it?

Where can I get it?

The combined oral contraceptive pill is usually just called the pill, or COC. There are many different types, but all contain two hormones - estrogen and progestogen. These are similar to natural hormones women produce in their ovaries.

The main way the pill works is by stopping the ovaries releasing an egg each month (ovulation). It also:

• Thickens the mucus in the cervix, making it difficult for sperm to reach an egg
• Makes the lining of the womb thinner so it is less likely to accept a fertilised egg

The pill's effectiveness depends on how carefully it's used - it's more than 99 per cent effective when taken according to instructions. This means that fewer than one woman in 100 using this method for a year will get pregnant.

Myth: The pill makes you put on weight
Fact: Not true - poor diet, lack of exercise and drinking too much alcohol contribute to weight gain
Myth: The pill makes you infertile
Fact: Not true – women who stop the pill get pregnant as easily as those who've never used the pill and you don't need 'regular' breaks off the pill

How do you use it?

The pill can be started up to and including the fifth day of a period. If taken at this time it is effective straight away. If started at any other time, additional contraception has to be used for seven days.

The pill is taken every day for 21 days until the pack is finished.

You then have a break of seven days when you have a bleed, which is usually shorter and lighter than normal periods. Everyday pills have 21 active pills and seven placebo tablets. These are taken without a break.

Advantages:

• Doesn’t interrupt sex
• Usually makes your bleeds regular, lighter and less painful
• May help with premenstrual symptoms
• Reduces the risk of cancer of the ovary, womb and colon
• Reduces acne in some women
• May protect against pelvic inflammatory disease
• May reduce the risk of fibroids, ovarian cysts and (non-cancerous) breast disease

Disadvantages:

Temporary side-effects at first may include:

• Headaches, nausea, breast tenderness and mood changes
• Breakthrough bleeding (unexpected bleeding on pill-taking days) and spotting

If these do not stop within a few months, changing the type of pill may help.

The pill can have some serious side-effects, but these are not common. They may include:

• Raised blood pressure
• A very small number of women may develop a blood clot which can block a vein (venous thrombosis) or an artery (arterial thrombosis, heart attack or stroke)
• A small increase in risk of being diagnosed with breast cancer
• A small increase in the risk of cervical cancer if the pill is used continuously for more than five years

The pill may not be suitable for all women, but for most women the benefits of the pill outweigh the possible risks.

The pill may be unsuitable if you:

• Think you might already be pregnant
• Smoke and are over 35, or are over 35 and stopped smoking less than a year ago
• Are very overweight
• Take certain medicines - always check
• Have had a previous thrombosis
• Have a heart abnormality, circulatory disease or high blood pressure
• Have very severe migraines or migraines with aura
• Have breast cancer now or within the last five years
• Have active liver or gall bladder disease
• Have diabetes with complications, or have had diabetes for more than 20 years

What to do if you forget a pill

• It's important to take the combined pill at a regular time each day
• You have 'missed a pill' if you take it more than 24 hours later than your usual time
• Missing one pill anywhere in the pack, or starting your pack one day late, is not a problem, but missing more than one pill or starting the packet more than one day late could affect your contraceptive cover - seek advice
• If you're sick within two hours of taking the pill it will not have been absorbed properly. Take another pill as soon as you feel well enough. If you continue to be sick, seek advice. If you have severe diarrhoea for more than 24 hours, this makes your pill less effective - seek advice

Other things to consider

• Initially,you'll be given three months' supply of the pill. If there are no problems you will then be given up to a year's supply
• You don’t need a cervical screening test or an internal examination to have the pill
• The pill does not protect you against sexually transmitted infections

The pill is free on the NHS from contraception clinics, sexual health clinics and your GP.

Advice and support

Call fpa's helpline on 0845 122 8690.

This article was last reviewed in July 2007.