Fibroids and Bleeding Between Periods: What You Need to Know

During their reproductive years, women experience a monthly menstrual cycle. The menstrual cycle is approximately 28 days long, made up of 4 stages: Menstruation, the follicular phase, ovulation, and the luteal phase. 

Menstruation (your period) lasts from approximately day 1 to 7 of your cycle (as long as pregnancy doesn’t occur.) During this time, the uterine lining and unfertilized egg shed through the vagina, which causes vaginal bleeding. The bleeding is typically quite heavy, often requiring some form of menstrual hygiene product, like pads or tampons. Some women also choose to wear period underwear during this time to safeguard against leaks.

Every woman’s cycle is different and rarely runs like clockwork. Fluctuations in cycle length and period flow is normal and to be expected. So, what’s not normal?

Heavy uterine bleeding in between periods is not considered normal and may require a visit to the doctor. When we say ‘heavy,’ we’re talking about more than just spotting. Heavy bleeding refers to bleeding that requires the use of a pad or tampon. 

Many things might cause heavy uterine bleeding between periods (and heavy menstrual bleeding too), including uterine fibroids. This article dives into what you need to know about fibroids, including:

• What they are
• Causes 
• Risk factors
• Symptoms 
• Diagnosis
• Treatments 

What Are Fibroids?

The Mayo Clinic describes uterine fibroids as “non-cancerous growths of the uterus that often appear during childbearing years.” These benign tumors are known to cause irregular periods and/or heavy bleeding between periods. 

In terms of size, uterine fibroids can be as small as a pea or as large as a grapefruit! Uterine fibroids can happen anywhere in or around the uterus and are only an issue if they grow large enough to put pressure on your reproductive organs and get in the way of their normal functioning.

Uterine fibroids are very common and often nothing to worry about—around 20%–50% of women will have them at one point or another during their reproductive years, according to John Hopkins. They are noncancerous most (99%) of the time. But, in the case of the other 1%, there are treatments available to help.

Types of Fibroids

Fibroids are all the same, but they can be categorized based on their location. There are 3 main places fibroids tend to grow.

What Causes Uterine Fibroids Is Relatively Unknown

We don’t know too much about what causes uterine fibroids. But, based on many clinical tests, it’s likely fibroids are closely related to:

• Hormones: It’s widely believed that fibroids are linked to a woman’s estrogen and progesterone levels. One study by the Journal of Community Hospital Internal Medicine Perspectives noted that fibroids start to shrink after women enter menopause—a time when estrogen levels drop. 
• Genetics: Many scientists believe that fibroid formation could also be linked to genetics, as mentioned in this study by the Journal of Reproductive Infertility. Also, fibroids contain genes that have mutated from the genetic makeup of normal cells.
• Vitamin imbalances: Studies from the Oxford Journals and the Journal of Women’s Health suggest micronutrient imbalances, like vitamin D and vitamin A, may be linked to fibroid development.

Risk Factors

Though the exact cause of uterine fibroids is still unclear, the medical world has a pretty good understanding of the risk factors that make someone more likely to develop them.

You’re more likely to develop fibroids if you:

• Are a female of reproductive age
• Are of African American heritage
• Are overweight
• Eat a diet high in red meats
• Don’t consume a lot of green vegetables, dairy, and fruits
• Have a high alcohol intake

Symptoms 

As mentioned, most women who have fibroids aren’t even aware of it. According to Harvard Health, approximately 25%–35% of women aged 35–50 experience symptoms due to fibroids. In rare cases, symptoms can be so severe that treatment—or even surgery—is needed.

The severity of symptoms depends on the number, size, and location of the fibroids. The most common sign of fibroids is heavy periods and bleeding between periods. If you experience that along with any of the following symptoms, it’s a good indication you have uterine fibroids, and you should visit your doctor to discuss whether medical treatment is needed.

• Very long and heavy menstrual periods (more than 7 days)
• Pelvic pain
• Pain in the back or lower legs
• Pain during sex
• Trouble peeing or pooping (this is a sign the fibroid is putting pressure on your bowels)
• Frequent urination

Pregnancy and Fibroids

Fibroids generally won’t prevent you from getting pregnant. However, submucosal fibroids can sometimes cause pregnancy loss or infertility. 

According to the Mayo Clinic, uterine fibroids may also increase your chances of complications during pregnancy, like placental abruption (when the placenta detaches from the uterus), fetal growth restriction (when an unborn baby remains smaller than average for a long portion of the pregnancy), or premature delivery.

If you want to get pregnant and have uterine fibroids, or are at high risk of developing them, speak to your doctor to explore your options.

Diagnosis & Tests of Fibroids

If you experience any of the symptoms mentioned above, you should see your doctor immediately to get tested for fibroids. Most uterine fibroids are detected during a routine pelvic exam. Your medical doctor will usually feel the mass while they examine you. Depending on what they detect, they may order more tests to examine the fibroid more closely.

Some common tests for uterine fibroids include:

• X-ray
• Ultrasound 
• MRI
• Blood test (to check for anemia due to extra blood loss between periods)
• Hysterosalpingography (this is an X-ray exam of the uterus and fallopian tubes that uses a special dye)
• Hysteroscopy (a doctor inserts a thin instrument up your vagina to visually examine the cervix and uterus)
• Endometrial biopsy (the doctor will remove a sample of the fibroid tissue to examine it more closely)

Treatment of Fibroids

Most uterine fibroids shrink over time on their own, especially as women approach menopause and levels of estrogen drop. So, if your doctor detects fibroids, they will most likely recommend a ‘wait and see’ approach. If you experience some minor pelvic pain, they might prescribe some anti-inflammatory painkillers.

If your symptoms are more severe, your doctor may recommend surgery and/or treatment for your fibroid(s). Your doctor will make the judgment call based on a variety of factors like the size of the fibroids, whether or not they are causing you a lot of pain, your age if you’re planning on getting pregnant, and your past health history.

As a last resort, your doctor may recommend one or more of the following more intense treatments, as outlined by John Hopkins Medicine:

• Medical menopause (a therapy that reduces your levels of estrogen, essentially inducing menopause)
• Anti-hormonal medicines (some medicines seem to oppose estrogen and have been used to treat fibroids)
• Minor surgery (fibroids are removed, but the uterus is left intact)
• Fibroid embolization (a newer technique that blocks off the arteries supplying blood to the fibroids; cutting off blood supply will shrink them)
• Hysterectomy (complete removal of the uterus; they will only do this in the most extreme cases)

Other Causes of Abnormal Vaginal Bleeding Between Periods

If you’re experiencing heavy bleeding between periods, it may be caused by something other than uterine fibroids. There are a host of other reasons why you may experience irregular bleeding, including:

• Birth control pills: Also known as breakthrough bleeding, light bleeding often occurs in the first 6 months of taking a new birth control pill, according to the American College of Obstetricians and Gynecologists
• Morning-after pill: According to the Mayo Clinic, the morning-after pill may cause abnormal uterine bleeding or heavy menstrual bleeding
• Intrauterine device (IUD): Some women with an IUD for birth control may also experience irregular bleeding outside the menstrual phase
• Medications: Certain medications may cause abnormal vaginal bleeding; your pharmacist should advise you if this is the case
• Infections: sexually transmitted infections (STIs) or pelvic inflammatory disease (PID) can also cause vaginal bleeding between periods
• Ectopic pregnancy or miscarriage: Irregular vaginal bleeding is a symptom of both ectopic pregnancy and a miscarriage
• Ovarian cysts: Ovarian cysts are fluid-filled sacs in or on the ovaries that can cause abnormal bleeding between periods and lead to conditions like polycystic ovary syndrome (PCOS)
• Blood clotting disorders: For example, von Willebrand disease prevents blood clots from forming as they should
• Cancer: Cancer or precancer of the reproductive organs may also cause abnormal bleeding
• Perimenopause & menopause: A drastic change in hormone levels causes women to experience abnormal bleeding, irregular periods, or skipped periods

In Summary

Uterine fibroids are often nothing to be concerned about and very common. If you experience symptoms caused by fibroids, you can talk to your doctor about treatment. However, unless the symptoms are very severe and reduce your quality of life or if you’re trying to get pregnant, it’s unlikely medical treatment will be required.

What to Do if You Experience Abnormal Bleeding

Having said that, if you notice heavy bleeding or abnormal bleeding between periods, irregular periods, abdominal pain and cramping, or unusual vaginal discharge, you should visit your doctor as soon as possible as something other than fibroids could be the culprit.

Written by Jane Flanagan — Updated on April 5, 2022.

We hope you found this post informative — but remember: we’re not doctors and this post is not medical advice! While all posts are fact-checked and well researched, we always recommend you chat with your doctor about any questions or concerns you might have regarding a medical condition. We’re here to support and educate, but never with the aim of disregarding professional medical advice you’ve been given. Phew, now that that’s out of the way, you can go on living unapologetically free.