Hormonal effects of Mirena

Women may be concerned about the effects of hormones on their body. However, as Mirena does not contain estrogens, estrogen-related hormonal adverse effects should not occur. The most commonly occurring adverse effects, which may be due to levonorgestrel, include headache (occurring in at least 1 out of 10 users) and migrane, depressed mood/depression, nausea, acne and hirsutism (occurring in less than 1 out of 10 users).

For a full list of adverse drug reactions that include those occurring in less than 1 in 10 women, see table 3 in the Mirena: Adverse Effects section (in the Indications for treatment with Mirena section).

Studies have demonstrated that Mirena is not associated with an increased risk of the development of breast cancer ¹. Since breast cancer is a hormone-dependent tumor, patients who have breast cancer should use non-hormonal methods of contraception, and breast cancer is a contraindication for Mirena use ².