Contraceptive agents types

Efforts to improve IUDs have led to the use of medicated devices. Two types of agents are generally used—contraceptive metals and steroid hormones. The metal device is exemplified by the CU-7, a polypropylene plastic device in the shape of the number 7. Copper is released by a combination of ionization and chelation from a copper wire wrapped around the vertical limb. This system is effective for up to 40 months. 

Rifampicin is a potent inducer of cytochrome P450 enzymes and thus can diminish the activity of a multitude of other agents such as warfarin, gluco-corticosteroids, cyclosporin, oral contraceptives and sulphonylurea-type oral antidiabetic agents. 

The hepatic veins may be affected by xenobiotic-induced occlusion resulting from thrombosis or from proliferation starting in the intima and subsequently producing (secondary) thrombosis. An occlusion of the large hepatic veins is known as the Budd-Chiari syndrome. There are two distinct types, the truncular and the radicular form, the latter corresponding to veno-occlusive disease, (s. p. 249) Contraceptives (J.A. Ecker et al., 1966) and cytostatic agents are held responsible. Women develop this type of hepatic disease more than twice as often as men. (s. fig. 29.9)... 

Epidemiology and aetiology Adenomas have an incidence of 4-10/100,000 inhabitants/year. They are almost exclusively found in women during their reproductive years. Children are rarely affected. (28) In men, the risk is higher when they take anabolic agents. In about 90% of cases, there is a correlation with the intake of oral contraceptives over many years this was pointed out for the first time by J.K. Baum et al. in 1973. (19, 21, 25, 31, 32) There is also an association with the polycystic ovary syndrome. (33) An adenoma can develop in glycogenosis types I and III (with multilocular nodulation) (29) as well as in type IV. (16) The administration of various other drugs (e.g. carbamazepine) has also been associated with adenomas. 

Co-administration of moclobemide with several types of oral contraceptives has not shown any significant interaction, and there does not appear to be any alteration in the efficacy of either agent. 

Although some of these substances originate as medicines, e.g. contraceptive steroids and some antimycotic agents, others arise from personal care products and industrial chemicals.This is a major area of concern for human reproductive health assessment, and one that deserves thorough investigation and consideration. Where these types of product are shown to have a veterinary origin, as is the case with the anabolic agents in countries where their use is permitted, then clearly measures to protect the environment and public health must be considered (see Chapter 13). 

In addition, the contraceptive exemplifies two other values of continuous, controlled delivery. One is the achievement of targeted drug delivery to a single organ (the uterus) of a type of agent (a birth control hormone) that previously had to be delivered system-ically to the whole body. The other is the ability to use—because of continuity of delivery—a biological substance (progesterone)... 

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