Hormonal Intrauterine contraceptive devices

There are numerous choices of contraception for women, and the efficacy and costs of each must be balanced when giving advice, both to the individual and to the community at large. Hormonal contraception is still the most effective method of fertility control, and in this section only hormonal contraception will be considered. However the relative merits of other methods such as intrauterine contraceptive devices (lUCDs), condoms, and vaginal or cervical caps should be kept in mind as alternatives. Condoms in particular have important advantages in limiting spread of sexually transmitted disease. 

A non-hormonal approach to emergency contraception is insertion of an intrauterine contraceptive device up to 7 days after ovulation in a cycle during which unprotected intercourse has occurred (13). 

Rivera R, Yacobson I, Grimes D. The mechanism of action of hormonal contraceptives and intrauterine contraceptive devices. Am J Obstet Gynecol. 

An innovative progesterone-containing device (Progestasert) has been made available as a long-lasting intrauterine contraceptive. It contains 38 mg of the drug in a silicone oil solution, which on proper insertion releases 63 jig of progesterone per 24 hours for periods up to 1 year. The contraceptive effects of the device itself (an intrauterine device, IUD) is believed to be enhanced by the hormone s local effect on the endometrium. 

The most well known commercial reservoir controlled release systems deliver hormones for contraception from hydrophobic polymers. The Norplant subcutaneous device controls the release of levonorgestrel with silicone rubber, and the Progestasert intrauterine device (lUD) releases progesterone from reservoir devices of ethylene vinyl acetate. In the field of insecticides, reservoir dispensers called BioLure were developed to provide zero-order release ofinsect pheromones to disrupt mating (Smith et al, 1983). The dispenser consists of a slab configuration with a rate-controlling membrane, with constant release described by Eq. 1. 

Only one implantable contraceptive preparation is available at present in the USA. Etonogestrel, also used in some oral contraceptives, is available in the subcutaneous implant form listed in Table 40-3. Several hormonal contraceptives are available as vaginal rings or intrauterine devices. Intramuscular injection of large doses of medroxyprogesterone also provides contraception of long duration. 

Use of spermicides in the vagina (They are used in combination with barrier methods. This is strictly chemical rather than hormonal contraception as also are intrauterine devices that contain copper, which is gametocidal). 

Spermicidal condoms emd intrauterine devices (lUDs) contmning copper or a hormone are medicines, whereas non-spermicidal condoms and other barrier-type contraceptives (e.g., diaphragms) cire medical devices. 

Women receiving anticonvulsants for a seizure disorder require special attention with regard to hormonal contraception. Giving a hormonal contraceptive concomitantly with phenobarbital, carba-mazepine, or phenytoin reduces the contraceptive s efficacy, and many anticonvulsants (e.g., phenytoin) are known teratogens. The use of condoms in conjunction with high-estrogen OCs, injectable progestin-only contraceptives, or intrauterine devices may be considered for these women. ... 

The oral contraceptives are of two main types the combined hormonal contraceptives containing both an oestrogen and a progestogen (monophasic, biphasie, triphasie, or sequential), available as tablets or a patch, and the progestogen-only contraceptives, which are available as tablets (sometimes ealled mini pills), parenteral preparations (implants, depot injections) and intrauterine devices. 

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