Study links hormonal IUD use to higher breast cancer risk in women under 50

A new Danish study found that women under 50 who used a hormonal IUD had a 40% higher risk of breast cancer compared to those who did not use hormonal contraceptives. The risk increased with longer use, reaching 80% for those using the IUD for 10-15 years. The study tracked 78,595 new users of the levonorgestrel-releasing IUD and matched them with non-users. Over nearly seven years, there were 1,617 new breast cancer cases, with 720 among IUD users and 897 among non-users. While the absolute risk remains low, the findings add to existing evidence linking hormonal contraception to breast cancer. The authors noted limitations, including potential underestimation of risk due to device removal before the end of recommended use.