Injection

What is it and how does it work?

Progestrogen hormone injections stop ovulation; thicken cervical mucus to stop sperm reaching the egg; and thin the lining of the womb to prevent a fertilised egg from implanting.

Effectiveness

Up to 99% effective

Who can have it?

Women of child bearing age, depending on consultation.

Advantages

Lasts for up to 14 weeks. For as long as the injection lasts, you don’t need to think about contraception to prevent pregnancy. Can help reduce heavy painful periods.

Disadvantages

Your periods may change (stop, last longer or become irregular). Can take up to a year for your fertility to return. Can cause some women to put on weight.