New Formulations of Oral Contraceptives
نویسندگان
چکیده
_________________________________________________________________________________ Since the 1960s, oral contraceptives were administered in a traditional 21/7 regimen. In recent years, new regimens (24/4, 84/7, and Lybrel) have reported that shortening the HFI decreases the risk of ovulation and unintended pregnancy. Recent literature also suggests that these regimens are associated with breakthrough bleeding and amenorrhea in extended and continuous-cycle regimens.
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