Over the years, much has been learned about uterine fibroids, including the various types, symptoms, who are most at risk, treatment options, and the steps women can take to limit their chances of developing them. Yet, researchers still aren’t entirely sure how to answer this one question: What causes uterine fibroids to grow? Since no one knows for sure what causes fibroids, we also don’t know what causes them to grow or shrink.
Uterine fibroids are non-cancerous growths that develop from the muscle tissue of the uterus. The majority are diagnosed in women between the ages of 35 and 54. However, fibroids can occur in women younger than 35 and until menopause. Depending on your situation, you may have one or several. Moreover, they could all differ in size and either stay that way or grow at different rates. The growth factor is of particular concern since uterine fibroids can become rather large and lead to painful, life-altering symptoms.
Do You Have Any of These Uterine Fibroid Symptoms?
- Painful periods, debilitating cramps, pelvic pain, and pressure
- Heavy or abnormal menstrual bleeding
- Painful intercourse
- Fatigue and weakness
- Bloating or swelling in the lower abdomen
- Back or leg pain
- Urinary frequency, constipation, diarrhea, and rectal discomfort
Hormones Are the Main Culprit in What Causes Fibroids To Grow
What causes fibroids to grow? Doctors and medical researchers can point to several factors that “may” cause growth, but we know with absolute certainty that they are under hormonal control—specifically, estrogen and progesterone. Furthermore, they tend to grow more rapidly during the reproductive years when hormone levels are at their highest.
According to the Office on Women’s Health (OWH), estrogen and progesterone stimulate the development of the uterine lining during each menstrual cycle in preparation for pregnancy. This causes fibroids to swell. Fibroids can also grow in clusters to create a large, heavy mass. In many cases, they can vary from the size of a pea or bean to a melon or grapefruit and cause swelling of the abdomen. Here is a breakdown of what is considered a small or large fibroid.
- Small fibroids — Between 1 cm and 5 cm. Basically, the size of a small seed to a cherry.
- Medium fibroids — Between 5 cm to 10 cm. Can be the size of a plum to an orange.
- Large fibroids — Greater than 10 cm. The size of a melon, grapefruit, watermelon, or a small pumpkin.
Most clinicians believe uterine fibroids shrink when a woman goes through menopause, which stands to reason since this is a period during which hormone levels are much lower. That said, complications due to excessive uterine fibroid growth can include pregnancy and labor complications, repeated miscarriages, and fertility problems.
According to the Office on Women’s Health (OWH), estrogen and progesterone stimulate the development of the uterine lining during each menstrual cycle in preparation for pregnancy.
What Other Factors Cause Uterine Fibroids To Grow?
Following are 11 factors that affect fibroid growth aside from hormones.
1. Heredity — Studies conducted over the past decade or longer show a consistent link between uterine fibroids and heredity. So, if your mother or sister had fibroids, you are predisposed. The OWH says your risk of experiencing them is roughly three times higher. Why is this the case? Read factor number two.
2. Genetics — While not all uterine fibroids develop from hereditary reasons, some develop because of genetics. In a study by The American Journal of Human Genetics, researchers analyzed genetic data and detected genetic variants associated with uterine fibroids. One of these genes was FASN, which encodes a protein called FAS (fatty acid synthase). Because of this study, physicians believe there is a genetic component to fibroid growth.
3. Age — Fibroids can form at any age, but they are more common between the ages of 35 and 54 since they grow throughout a woman’s reproductive life. As hormone levels decrease over the age of 54 and after menopause, uterine fibroids can stop growing or even shrink, as previously stated.
4. Ethnicity — Black women are three times more likely to develop fibroids than any other ethnic group. In fact, 80% of Black women will develop fibroids by the time they are 50. The rate of hospitalization for fibroids is three times higher for Black women than white women. They are also two to three times more likely to undergo a hysterectomy and seven times more likely to have a myomectomy.
5. Vitamin D deficiency — One well-established fibroid risk factor we know about besides being Black is Vitamin D deficiency. Vitamin D deficiency is not life-threatening, but it is linked to fibroids, so much so that women with sufficient Vitamin D levels had an estimated 32% lower odds of fibroids than those with Vitamin D insufficiency.
6. Certain foods/diet — Women who eat red meat and sugary foods are linked to a higher risk of uterine fibroids, regardless of whether or not they are related to someone with fibroids. This diet can also lead to weight gain.
7. Obesity — Obesity is a risk factor for fibroid growth and contributes to telltale fibroid symptoms such as back and pelvic pain. According to the OWH, the risk for heavy women is two to three times greater than average. A healthy BMI, or Body Mass Index, is between 18.5 and 25.
8. Hair relaxers — Several studies suggest chemicals in hair relaxers increase a woman’s risk of developing uterine fibroids as well as certain uterine cancers. This is because hair straighteners and relaxers can cause burns, lesions, and breaks in the scalp’s skin, allowing the chemicals to be absorbed into the body. Researchers point to these products as containing dangerous carcinogens or hormone disruptors that affect a woman’s reproductive system if used consistently over many years.
9. Phthalates — According to information from the U.S. Centers for Disease and Prevention, phthalates—also called plasticizers—are a group of chemicals designed to make plastics more durable. They can be found in hundreds of products, including soaps, shampoos, hairspray, food storage containers, plastic packaging, etc. The problem is that they don’t bind to other materials and can end up in our bodies. As a result, they can trigger the growth of uterine fibroids and delay the rate at which they die.
10. Birth control pills — Many women don’t know this, but birth control methods can feed existing fibroids and help them grow. Some studies show birth control pills can help with certain side effects of existing fibroids, but it’s worth noting that being on a regular birth control routine puts you at risk for uterine fibroids. Talk to your gynecologist to make sure the type you use is the best option for your situation.
11. Stress — Stress is the body’s biochemical response to life challenges. To handle stress, the brain tells our body to produce extra hormones. As a result, hormone levels rise, which stimulates fibroid growth and causes symptoms.
Women with sufficient Vitamin D levels had an estimated 32% lower odds of fibroids than those with Vitamin D insufficiency.
Ways You Can Reduce Your Risk of Uterine Fibroids
- Eat more fruits, especially citrus, and vegetables.
- Get more exercise.
- Avoid consuming too much alcohol.
- Drink more dairy.
- Avoid alcohol.
- Discuss birth control options with your doctor.
- Increase your Vitamin D intake.
- Lower your stress levels.
A True Fibroid Treatment Partner: 100% Fibroid-Focused Practice
Uterine fibroids can cause painful and life-altering symptoms for many women, especially as they get larger and put more pressure on your uterus. At Fibroid Institute, we do not believe you need to decide between suffering in silence and having invasive surgery. If you suffer from painful uterine fibroids, schedule a telehealth or office consult.
Our team is always on hand to partner with you and your doctor to determine the best course of action for you. As board-certified interventional radiologists our Houston and Dallas fibroid doctors help thousands of women avoid fibroid surgery and find relief from their fibroid symptoms. We are dedicated to treating fibroids using uterine fibroid embolization (UFE), the gold standard in non-surgical fibroid treatment.
With multiple locations, our Houston and Dallas fibroid clinics help thousands of women avoid fibroid surgery and find relief from their fibroid symptoms.
Request a free 10-15-minute phone screening to determine if you are a candidate. If you qualify for UFE after the screening, you can schedule your on-site or telehealth consultation at our 100% fibroid-focused practice. Most major medical insurance providers cover the cost of UFE.
To become #FibroidFree get started now with Fibroid Institute Dallas at 214-838-6440 or with Fibroid Institute Houston at 713-903-3733 or complete the form below.
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Before starting any new treatment or if you have questions regarding a medical condition, always seek the advice of your doctor or other qualified health provider. This information is not a substitute for professional medical advice.
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