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Methods for Studying Uterine Contributions to Pregnancy Establishment in an Ovariectomized Mouse Model
Published on: April 7, 2023
[Update on the progestin-only contraception]
1Clinique de la Muette, 46, rue Nicolo, 75016 Paris, France.
Abstract:
Despite the lack of complete data concerning their effects, the use of progestin-only contraception is increasing in France (particularly the intra-uterine device, the subdermal implantation, and microprogestins). These prescriptions include a broad range of molecules and administration of doses. In some cases, prescriptions of progestogens are made out of the marketing authorisation indications (especially for macroprogestins). For all of these reasons, an Expert Advisory Board has been set up in order to answer the 35 questions addressed by an Expert Organization Board. The choice of these questions was based on controversial or nonconsensual points usually encountered in everyday clinical practice. When possible, answers given were strongly supported by data issued from medical literature. In situations where clinical studies were lacking, the Expert Advisory Board answered in the most consensual way. All answers given by the Expert Advisory Board were subsequently submitted to the Expert Assessment Board before the latest validation of this document. The progestogen only contraception has different levels of action (local and/or central) which may vary from one drug to another. Its prescription is granted satisfactory efficacy (the macroprogestins' efficacy has never been evaluated) but requires a strict pill-taking routine (especially for the microprogestin contraception). It has never been demonstrated that the use of progestogen is associated with an increased risk of breast cancer. Nevertheless, analysis of breast cancer and progestogen studies should be carried out carefully. Even though the effects, often misunderstood, of the different progestogens on mineral bone density are likely to vary according to the molecules, in particular due to the plasma estradiol level, there is no direct argument for considering the progestin only contraception as a fracture risk factor. As for the venous thromboembolism risk, progestogens are not considered to be risk factors. The progestogen only contraception is advised in the following cases: bad tolerance of exogenous oestrogens; in order to counteract an endogenous hyperoestrogenosis; metabolic or cardiovascular contraindications to estroprogestin; hormonal fluctuations generating premenstrual dysphoria or catamenial headaches. Lastly, the progestin-only contraception should be used as a prime contraception in some particular situations (breast feeding, adenomyosis...).
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