The combined pill

What is it?
The combined pill is a tablet that contains the hormones oestrogen and progestogen (synthetic versions of the hormones that are naturally released from the ovaries). You take the pill every day for 21 days, then stop for seven days. During that week, you have your period. After seven days, you start taking the pill again.

How does it work?
The hormones prevent you from ovulating (releasing an egg). They also make it difficult for sperm to reach an egg, or for an egg to implant itself in the lining of the womb.

How effective is it?
If used correctly, it can be more than 99% effective. This means that less than one woman in 100 who takes the pill will get pregnant in one year. The chance of getting pregnant rises if:

• the pill isn't taken according to the instructions,
• it doesn't stay in the body long enough to work, for example, when you vomit, or
• other medications make it less effective.

Added benefits?

• You don’t ovulate when you take the combined pill, so you don’t have a real period every month. Instead, you get a withdrawal bleed, which can be much lighter and shorter than a period. If you have problems with heavy, painful periods, taking the combined pill can help.
• It can protect against cancers of the ovary, womb and colon, and some pelvic infections.

What else should I know?

• To be effective, it must be taken at the same time every day, and on the correct days.
• You could get pregnant if you don’t take it at the same time every day, you miss one, you vomit or have severe diarrhoea, or you take other types of medication.
• It isn’t suitable for women over 35 who smoke, or women with certain medical conditions. Your doctor or nurse can tell you whether you can take this kind of pill. 
• There's a very low risk of serious side effects, including blood clots and cervical cancer.
• Minor side effects include mood swings, breast tenderness and headaches.
• There's no evidence that the combined pill causes women to gain weight.

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