What Are Uterine Fibroids?

What are fibroids? First of all, what causes them? What can we do about them? Fibroids, the medical term is called leiomyomata. You know, I don't know why we have to have big fancy words for everything, but the word means it's a muscle tumor. So we have two parts of our uterus that we have, the muscle myometrium part. That is what grows when you get pregnant and houses the baby. And then there's the endometrial lining, which is the endometrium that grows every month and responds to estrogen and progesterone, and then you shed off and bleed as a period. So that comes and goes every month. Whereas the myometrium should stay pretty stable. Those muscle cells, sometimes the endometrial cells can get into the muscle cells, and that's called adenomyosis. That's a WHO tissue. But essentially, these myometrial cells, they start to grow tumors inside of them called leiomyomas. And those are fibroids. So fibroids are very circular, they're very dense, they're heavy, and they have a lot of blood supply to them. They're almost always benign. It's very rare to have malignant fibroids. Those usually grow quickly. They don't have a nice uniform pattern to their growth. They look very disoriented and heterogeneous on ultrasound or mri. So there's some differences to them, but the only way to know for sure is to give it to the pathologist. They look under the microscope and they can tell you whether it's benign or malignant. But fibroids are always, almost always benign growths of the muscle of the uterus. They can grow right into the meat of the myometrium. They can grow hanging off of it. It's called a pedunculated fibroid. They can grow pushing out toward the outside of it. That is called a subserosal fibroid. They can grow into the cavity where the endometrium is growing, where that's where the baby would potentially implant and grow. That's called submucosal sub. So sometimes it even grows into the cervix, which is the bottom part of the uterus. So fibroids can grow all over the place. They have different names depending on where they're growing. It's really common for women to have fibroids and not even know it. There's evidence that up to 75% of women have fibroids, and it's even higher in the African American community. When autopsies are done, they realize that a lot of women have fibroids and never knew it. So it's not usually a concern. But it becomes a concern if you have so many of them that your overall uterus gets to be enlarged or you have fibroids that are themselves really large.