Oral contraceptives, biphasic monophasic, triphasic, progestin

Oral Contraceptives, Biphasic, Monophasic, Triphasic, Progestin Only (Table VI-4) [Progestin/Hormone] WARNING ... 

Estrogens and progestins (combination oral contraceptives) are used as oral contraceptives. There are three types of estrogen and progestin combination oral contraceptives monophasic, biphasic, and triphasic. The monophasic oral contraceptives provide a fixed dose of estrogen and progestin throughout the cycle The biphasic and triphasic oral contraceptives deliver hormones similar to the levels naturally produced by the body (Table 52-1). 

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