This guide to choice of oral contraceptives, for U.S. clinicians, includes a review of the available types of pills, the pharmacology of the steroids in pills, safety issues regarding thrombosis, arterial disease and hypertension related to estrogens and progestins in pills, common side effects, and therapeutic uses of orals. Choice of an oral contraceptive narrows down to which of the 5 available progestins and their formulation, since all contain ethinyl estradiol as the estrogen. While Briggs' theory espoused picking a pill with the minimal metabolic effect, recent evidence suggests that some estrogenic activity may be preferable to the unopposed progestagen, actually an anti-estrogenic receptor effect, to prevent adverse lipid and blood pressure effects in users. Current pills with low doses of estrogens probably are not significant risks for women as regards thrombosis, particularly if predisposed women and smokers are excluded. Pills containing 0.35 mg ethinyl estradiol and 0.5 mg norethindrone, based on large population trials, are probably the minimal effective dose yet even these are more effective than most other contraceptive methods. Breakthrough bleeding and spotting have been further minimized, however, with multiphasic pills. It is best to start with a 0.30-0.35 mg estrogen oral contraceptive, such as Loestrin, Demulin, Orthonovum 1.35, Orthonovum 7/7/7 or Nordette, encouraging the patient to accept early side effects for 3 months before switching to others. Disorders that can be managed with oral contraceptives include recurring and pre-existing ovarian cysts, endometriosis, dysfunctional uterine bleeding and dysmenorrhea. Brief guidelines for handling normal side effects and treatment of the above disorders are included.
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