Combined Pill

How effective?

Over 99% effective if taken according to instructions. Less than 1 woman in 100 will get pregnant in a year

How it works

Contains oestrogen and progestogen. It stops ovulation, thickens cervical mucus to prevent fertilisation and thins the lining of the uterus to prevent an egg implanting

Advantages

Can reduce bleeding, period pain and pre menstrual tension. Protects against cancer of the ovaries and uterus and some pelvic infections. Suitable for healthy non-smokers up to the menopause. Normal level of fertility returns on cessation

Disadvantages

Not suitable for smokers over 35 and some other women. Very low risk but serious side effects may include blood clots (thrombosis), breast cancer and cervical cancer. Can have temporary minor side effects

Comments

May not be effective if taken late or after vomiting or diarrhoea. Some medicines can make it less effective. Pill users increase their risk of heart disease if they smoke