Is amenorrhea common when using the oral contraceptive micronor (norethindrone)?

Less than 5%: In patients on combined hormonal contraception, amenorrhea may occur in less than 5% of patients and is no cause of alarm. Micronor (norethindrone) is a progestin only pill and can also cause a lack of bleeding due to suppression of the uterine lining. As long as a pregnancy test is negative, there should be no further evaluation.