The influence of drugs on the contraceptive efficacy of Mirena has not been studied. The metabolism of progestogens may be increased by concomitant use of substances known to induce drug-metabolizing liver enzymes, specifically cytochrome P450 enzymes.
Mirena is contraindicated when one or more of the following conditions exist:
Pregnancy or suspicion of pregnancy.
Congenital or acquired uterine anomaly including fibroids if they distort the uterine cavity.
Acute pelvic inflammatory disease or a history of pelvic inflammatory disease unless there has been a subsequent intrauterine pregnancy.
Postpartum endometritis or infected abortion in the past 3 months.
Known or suspected uterine or cervical neoplasia or unresolved, abnormal Pap smear.
Genital bleeding of unknown etiology.
Untreated acute cervicitis or vaginitis, including bacterial vaginosis or other lower genital tract infections until infection is controlled.
Acute liver disease or liver tumor (benign or malignant).
Conditions associated with increased susceptibility to pelvic infections.
A previously inserted IUD that has not been removed.
Hypersensitivity to any component of this product.