Progestin preparations

Progestin preparations. Depot formulations for Lm. injection are 17-a-hydroxy-progesterone caproate and medroxyprogesterone acetate. Preparations for oral use... 

Adverse effects. After long-term intake of estrogen/progestin preparations, increased risks have been reported for breast cancer, coronary heart disease, stroke, and thromboembolism. Although the incidence of bone fractures also decreases, the risk-benefit relationship is unfavorable. Concerning the adverse effects of oral contraceptives, see p. 252. 2005 Thieme and conditions of license. 

In monophasic preparations a fixed estrogen/progestin combination is present in each contraceptive pill. 

Sequential preparations contain only estrogens in the first and a fixed estrogen/progestin combination in the second phase of the application period. 

As has been mentioned, preparation of esters of the C-17 hydroxyl group of selected progestins affords compounds with prolonged action. Similar chemical treatment of a corticoid would almost certainly lead to an ester of the sterically more accessible primary alcohol at C-21. In an interesting method for achieving esterification of the more hindered and less reactive tertiary 17-hydroxyl, prednisolone... 

The ketahzation of [4- F]fluoroacetophenone required a careful adjustment of reaction conditions [175]. It has been carried out in order to prepare fluorine-18 labelled progestin ketals, potential imaging agents for breast tumours. 

Minipill. Continuous low-dose administration of progestin alone can prevent conception. Ovulations are not suppressed regularly the effect is then due to progestin-induced alterations in cervical and endometrial function. Because of the need for constant intake at the same time of day, a lower success rate, and relatively frequent bleeding anomalies, these preparations are now rarely employed. 

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