Although modern contraceptives have drastically changed women’s lives, they are not risk free.
The Journal of Obstetrics and Gynecology released a study that found that the levonorgestrel-releasing intrauterine system (LNG-IUS) or progesterone-releasing IUD may be linked to a higher risk of breast cancer.
Originally this form of IUD was developed as a contraceptive. Later, however, it was also used as treatment for women who suffer from heavy periods as well as endometriosis and chronic pelvic pain.
Progesterone is a hormone that is naturally produced in a woman’s body. It regulates ovulation. Levonorgestrel is synthetic progesterone.
The hormone causes changes to the uterine lining and mucus in the cervix which makes it harder to sperm to reach the uterus. The harder it is for the sperm to reach the uterus, the more difficult it is to conceive.
Because the hormone strengthens the uterine lining, it helps cut down on heavy bleeding.
Levonorgestrel is also the hormone used in the morning after pill, Plan B contraceptive.
Finnish researchers in the Department of Obstetrics and Gynecology at the Hyvinkaa Hospital in Hyvinkaa, Finland examined the link between premenopausal use of the IUD and cancer rates.
Researchers followed more than 93,000 Finnish women between the ages of 30 and 49. All of the women were using the hormone releasing IUD to treat heavy menstrual cycles from 1994 to 2007.
The study discovered that over time the device did no significantly increase the risk of uterine cancer or ovarian pancreatic and lung cancer. However, researchers found that there was a spike in the number of breast cancer cases compared to women in the general population who were not using this particular IUD.
To be clear, the research does not demonstrate that the IUD causes breast cancer.
According to the lead author of the study, one limitation of the study was that women suffering from heavy menstruation may in fact represent a selected group of women who may have other risk factors for cancer.