What is adenomyosis?
Adenomyosis is a condition in the uterus that makes it get thicker. Adenomyosis causes the tissue that lines the uterus to grow into the surrounding tissues.
Normally, the inside of the uterus is lined with endometrial tissue. During a period, this tissue is shed by the body. For someone with adenomyosis, this tissue doesn’t remain inside the uterus. Instead, it grows into the muscular wall of the uterus (the myometrium) and makes it thicker. Even though the tissue is growing in the wrong place, it continues to respond to the cycles of hormones. During each menstrual cycle, it thickens, sheds, and bleeds. This can lead to an enlarged uterus and painful, heavy periods.
How common is adenomyosis?
Adenomyosis doesn’t get as much attention as endometriosis, but adenomyosis is not a rare condition. If you want to learn more about the differences between the two, check our our guide on adenomyosis vs endometriosis. Adenomyosis occurs in 22 to 24.4 percent of people who can’t get pregnant and around 20 percent of the general population.
The exact number of those who have adenomyosis isn’t known, but it’s estimated that between five and 70 percent of people who have a uterus have the condition in some form.