Rational prescribing of oral contraceptives

Abstract

Oral contraceptives are amongst the most popular drugs, at present about 60 million women are using this highly effective form of contraception. Following the classic demonstrations by Pinchus and Rock (1958) interest has centred on progesterone-oestrogen combinations as oral contraceptives. The first oral contraceptives to be introduced contained high doses of oestrogen and progesterone. Since then there has been a gradual, but signifi- cant reduction in both components, leading to a decrease in adverse effects. A large number of oral contraceptive pill formulations are available with an even greater number of proprietary preparations (Kestelman, 1981). Further preparations are being developed (Eyong, 1987). Many women appear to be suited by any pill formulation they are offered, but some find only one formulation acceptable. Unfortunately there are no simple rules for identifying which formulation is suitable for a particular patient, and if the first choice of oral contraceptive formulation proves unsuitable, the second choice must be better and based on the knowledge of the composition of available varieties and the relationship to each other.