ABSTRACT
The global population is estimated to reach 8.9 billion by 2050 and with it are significant risks of overpopulation. The goals of contraception are ultimately to reduce the number of unplanned and unwanted pregnancies by safe, well-tolerated and reversible methods. In the UK 25% of women aged 16-49 years and 50% of women in their twenties are on the combined oral contraceptive pill (COCP). Currently all pharmacological methods of contraception are reversible and made from synthetic steroids, containing no natural oestrogens or progesterones. The UK Medical Eligibility Criteria for the COCP is printed in summary in the guidance of the Royal College of General Practitioners’ Faculty of Sexual and Reproductive Healthcare on prescribing the combined contraceptive pill. Since the 1980s, the accepted risk for VTE due to COCPs was 30 in 100 000. Therefore, studies necessarily suggest an increased risk in third-generation pills but, rather, a reduced risk, an increased risk with second-generation pills compared with what was originally thought.
