Hormonal contraception: what is new?

Hormonal contraception has become more effective and more widely used, while the world population has grown from 3000 million in 1960 to 6000 million in 2000. There is a need for improved contraception, because legal abortion is used in a high proportion of pregnancies and illegal abortion continues to be common in some countries. Hormonal contraception now includes different choices of administration and dose regimens. The best selection depends on the benefits and risks of the method and whether there is a medical disability. Medical eligibility for combined oral contraceptives has improved during the past 40 years so that, for most women, all currently available low-dose products are safe. For women with medical conditions, wider eligibility for oral contraceptive use has evolved from better knowledge of the risk factors. The long-term risks of rare cardiovascular and malignant adverse events remain controversial. There are long-term benefits, however, as oral contraceptive use appears to protect against endometrial, ovarian and colorectal cancers. Emergency contraception provides an option that reduces the number of unplanned pregnancies with little or no long-term risk. Endometrial contraception is an option that would ideally have no influence on ovarian function or the bleeding pattern, and cause no significant side-effects. Hormonal male contraception, with indirect suppression of spermatogenesis by decreasing gonadotrophin output, is a further choice. Although hormonal contraception is effective and safe, many research investigations remain to be carried out in order to improve tolerance and achieve wider utilization.