Hormonal and non-hormonal methods of contraception

Hormones can be used as a contraceptive to prevent pregnancy by disrupting the menstrual cycle. Some oral hormone contraceptive pills prevent ovulation. If no egg is released, fertilisation cannot take place. Reasons why hormone pills may not be 100% effective (e.g. missing/late dose, taking after ovulation). Non-hormonal contraceptives act as a barrier to prevent sperm from reaching the egg, so fertilisation cannot occur. Evaluating benefits and risks of hormonal and non-hormonal (barrier) methods of contraception (including STIs).