Uterine fibroids, also called leiomyomas or myomas, are noncancerous growths in or on the uterus that often appear during a woman’s childbearing years. They aren’t associated with an increased risk of uterine cancer, and they rarely develop into any form of cancer.
Fibroids range in size from tiny spots invisible to the human eye to bulky masses that enlarge and distort the uterus. You can have one fibroid or many. Many women develop fibroids at some point, but they might not know it because there often aren’t symptoms, especially if they’re small.
Usually your doctor discovers them during a pelvic exam or a prenatal ultrasound.
Hany H Ahmed, MD, is an experienced, board-certified OB/GYN in Houston, Texas, who provides comprehensive women’s health services and specializes in normal and high-risk pregnancy care.
He gets asked a lot about uterine fibroids and if they interfere with getting pregnant and carrying a baby to term. So he put together this guide on the topic. Here’s what you need to know.
The causes of uterine fibroids
Doctors don't know the exact cause of uterine fibroids, but research suggests the factors involved include genetic changes, hormones like estrogen and other growth factors, and extracellular matrix (ECM), the material that makes cells stick together.
It’s believed that uterine fibroids develop from a stem cell in the uterus’ smooth muscle tissue (myometrium). This pluripotent cell divides repeatedly, creating a firm, rubbery mass different from the surrounding tissue.
The tissue may grow slowly or quickly, or it may not change at all. Many fibroids present during pregnancy shrink or disappear after birth, as the uterus returns to its normal size and hormone levels diminish.
Symptoms and complications of uterine fibroids
Not all women with fibroids have symptoms, but for those who do, the most common include:
- Heavy periods
- Periods lasting more than a week
- Pelvic pain or pressure
- Frequent urination
- Difficulty emptying the bladder
- Back or leg pain
If you have pain that doesn’t go away or comes on suddenly, or bleeding between your periods, especially if it’s heavy, see your doctor immediately.
Uterine fibroids usually aren't dangerous, but they can cause discomfort and lead to such complications as heavy vaginal bleeding and a subsequent drop in red blood cells (anemia).
Uterine fibroids and pregnancy
Fibroids usually develop before pregnancy, and they don't often interfere with your getting pregnant. However, it's possible that some fibroids — especially those that are submucosal and bulge into the uterine cavity — could cause infertility or pregnancy loss.
Most pregnant women who have fibroids experience no complications because of them. For the 10% to 30% who do end up having complications, the most common are abdominal pain and light vaginal bleeding. The baby won’t be affected unless you have substantial bleeding.
Even if you do experience fibroid symptoms or complications, they most likely won't affect the baby. However, your risk of miscarriage and premature delivery does increase slightly.
In addition, fibroids can cause the fetus to be in an abnormal position for delivery, stall labor, or, if they're located in or near the cervical opening, block the baby's passage. All these problems are rare, and they can all be solved by a cesarean delivery.
The bottom line? If you have uterine fibroids and want to get pregnant, you should be able to, assuming you don’t have any other medical condition that would prevent it. And if you’re already pregnant, you should be able to have a normal birth.
The best way to ensure you have no problems is to schedule regular well-woman exams with Dr. Ahmed, and to follow his instructions once you’re pregnant to keep yourself and your baby healthy.
To make an appointment, give us a call at 713-489-3348, or you can schedule online.