Understanding Uterine Fibroids: Causes, Symptoms, and Types

What Are Uterine Fibroids?

Uterine fibroids are the most common benign tumors found in women of reproductive age. Studies estimate that up to 70–80% of women will develop fibroids by the age of 50, though many will remain asymptomatic​. These tumors are hormonally sensitive, meaning they grow in response to estrogen and progesterone.

Fibroids can be singular or multiple and can grow at different locations within the uterus. Their growth rate varies from person to person, with some remaining small for years while others expand rapidly.

Causes of Uterine Fibroids

The exact cause of fibroids is unknown, but several factors contribute to their development:

1. Hormones

Estrogen and progesterone, the two primary female reproductive hormones, stimulate the growth of fibroids. This explains why fibroids tend to shrink after menopause when hormone levels decline​.

2. Genetics

Fibroids often run in families. If a close relative, such as a mother or sister, has fibroids, the risk of developing them is higher. Certain genetic mutations have also been linked to fibroid growth​.

3. Ethnicity

Studies show that fibroids are more common and tend to develop at a younger age in Black women compared to women of other ethnic backgrounds​. Additionally, fibroids in Black women are often larger and more symptomatic.

4. Obesity and Lifestyle Factors

• Obesity: Excess body weight increases estrogen production, which can stimulate fibroid growth.

• Diet: High consumption of red meat and processed foods has been associated with a higher risk of fibroids, while diets rich in green vegetables, fruits, and dairy may reduce the risk​.

• Alcohol and Smoking: These habits can disrupt hormone levels and contribute to fibroid growth.

5. Pregnancy and Childbirth

Women who have given birth tend to have a lower risk of developing fibroids. Pregnancy increases progesterone levels, which may play a role in reducing fibroid growth​.

Symptoms of Uterine Fibroids

Many women with fibroids experience no symptoms, but for those who do, symptoms can be severe and disruptive. The symptoms depend on the size, number, and location of the fibroids.

1. Heavy Menstrual Bleeding (Menorrhagia)

• One of the most common symptoms of fibroids is prolonged or heavy menstrual bleeding, which can lead to anemia and fatigue.

2. Pelvic Pain and Pressure

• Large fibroids can cause chronic pelvic pain, pressure, or a feeling of heaviness in the lower abdomen.

3. Frequent Urination or Difficulty Emptying the Bladder

• Fibroids that press against the bladder can lead to increased urination or difficulty in completely emptying the bladder.

4. Constipation and Bloating

• Fibroids that grow towards the back of the uterus may press against the rectum, causing bloating, constipation, and discomfort during bowel movements.

5. Pain During Intercourse (Dyspareunia)

• Depending on their location, fibroids can cause pain during sexual intercourse.

6. Infertility and Pregnancy Complications

• While most women with fibroids can conceive normally, some may experience infertility, recurrent miscarriages, or complications during pregnancy, such as preterm labor or abnormal positioning of the baby​.

Types of Uterine Fibroids

Fibroids are classified based on their location within the uterus.

1. Intramural Fibroids

• The most common type of fibroid.

• Develops within the muscular wall of the uterus.

• Can grow large and cause heavy periods, pelvic pain, and pressure on nearby organs.

2. Submucosal Fibroids

• Develop inside the uterine cavity, beneath the endometrial lining.

• Causes excessive bleeding, fertility issues, and miscarriage risk.

3. Subserosal Fibroids

• Located outside the uterus, growing towards the pelvic cavity.

• Can become very large, leading to pressure on the bladder or rectum.

4. Pedunculated Fibroids

• Fibroids that grow on a stalk-like structure, either inside (submucosal) or outside (subserosal) the uterus.

• Can twist and cause severe pain if blood supply is cut off.

5. Cervical Fibroids

• A rare type that grows in the cervix (the lower part of the uterus).

• Can cause difficulty during labor and delivery.

When to See a Doctor

Women experiencing any of the following symptoms should seek medical attention:

· Heavy or prolonged menstrual bleeding

· Severe pelvic pain or pressure

· Difficulty urinating or constipation

· Painful intercourse

· Infertility or recurrent miscarriages

Doctors may use ultrasound, MRI, or hysteroscopy to diagnose fibroids and determine their size and location​.

Conclusion

Uterine fibroids are a common yet often misunderstood condition that affects millions of women worldwide. While many fibroids are asymptomatic, others can cause significant discomfort and complications. Understanding their causes, symptoms, and types is crucial in making informed health decisions.

If you suspect you have fibroids, consult a healthcare provider to explore treatment options ranging from lifestyle modifications to medical and surgical treatments​​.

References

1. Micić, J., et al. (2024). "Currently Available Treatment Modalities for Uterine Fibroids." Medicina, 60(868).

2. Krzyżanowski, J., et al. (2024). "Advancements and Emerging Therapies in the Medical Management of Uterine Fibroids." Med Sci Monit, 30(e943614).

3. Li, H., et al. (2024). "The Influence of Uterine Fibroids on Adverse Outcomes in Pregnant Women: A Meta-Analysis." BMC Pregnancy and Childbirth, 24(345).