[Classification of oral contraceptives and its practical application to choice of prescriptions]

The authors have tried to classify the oral contraceptives at present in use throughout the world by their respective levels of oestrogenic and progestogenic components, taking into consideration also the relative strength of each product in use. They have based this classification on their personal experience of the several oral contraceptive products and on a profound study of the international literature. In this way it is possible to define a place for each oral contraceptive so that it can be chosen for the best possible use of a particular product for the hormonal background of the person using the contraceptive. It is true that changes have to be made to work out the oral contraceptives used for masses of people, but on the other hand in countries where there is sufficient medical personnel and education so that it is possible to think out and to prescribe for an individual, it seems to us useful that the doctor who is prescribing should try to adjust the oral contraceptive to the hormonal climate of the woman seeking it. This is true not only for the first time a prescription is made but in cases where by the accident of failure to tolerate the product something must be done to correct the troubles that are so often found in the first months after starting to use contraceptive products. This study includes a general picture of all oral contraceptives in which the products have been classified according to the total dose of oestrogens administered and according to the proportions of progesterone to oestrogens which make up the hormonal climate of the product. On the other hand this study also includes a list of the observations to make in order to adapt the oral contraceptive to the side-effects shown after the first prescription. The authors have come to the conclusion that by adapting the choice of a particular oral contraceptive to the woman who is to receive it interruptions in taking the contraceptive because of side-effects should be avoided. So unwanted pregnancies will be avoided and also the termination of these unwanted pregnancies.