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Published by Floriva · Updated 2026-04-28 · How Floriva checks its guides
Uterine Fibroids: Symptoms, Cycle Effects, and What to Track
Uterine fibroids can cause heavy periods and pelvic pressure. Symptoms vary by fibroid location. Here's what to recognize and what to log for medical care.
Uterine fibroids are the most common noncancerous growths of the female reproductive system, and they cause widely varying symptoms depending on their size, number, and location. Heavy periods are the most frequent complaint; detailed tracking of flow volume, pain, and cycle length gives healthcare providers the information needed to guide treatment decisions.
What Fibroids Are and Who Gets Them
Uterine fibroids (also called leiomyomas or myomas) are the most common noncancerous growths of the uterus. They develop from the smooth muscle cells of the uterine wall and can grow as a single fibroid or in clusters. Their prevalence is high. The majority of people with a uterus will develop at least one fibroid at some point during their lifetime, though many never know it because symptoms are absent.
They are not cancer and do not become cancer. The risk of a uterine sarcoma, a cancerous uterine tumor, is very low and is distinct from fibroid disease.
This guide is for educational purposes only and is not a substitute for medical advice.
How Fibroids Affect the Menstrual Cycle
Heavy Bleeding
The most disruptive symptom for most people is menorrhagia, heavy menstrual flow. The mechanism varies by fibroid type:
Submucosal fibroids increase the surface area of the uterine lining, producing more tissue to shed and interfering with the normal muscular contractions that limit bleeding. They also compress the blood vessels that would otherwise restrict flow.
Intramural fibroids can prevent the uterus from contracting efficiently, allowing more blood to escape during menstruation.
Subserosal fibroids rarely affect bleeding volume significantly.
Heavy periods from fibroids typically worsen over time rather than fluctuating. What begins as a heavier-than-usual period can progress to soaking through pads and tampons in an hour, passing large clots, and experiencing cycle-related anemia (fatigue, dizziness, pallor).
Longer Periods
Fibroids can extend the duration of menstruation beyond the person's previous baseline. A period that was five days may become seven or eight. Combined with heavier flow, this substantially increases total blood loss per cycle.
Cycle Timing Changes
Submucosal fibroids in particular can cause breakthrough bleeding or spotting outside of the expected period. Larger fibroids may alter uterine tone and hormone metabolism in ways that affect cycle regularity.
Pelvic Symptoms
Depending on location and size, fibroids can cause:
Chronic pelvic pressure or a sensation of heaviness in the pelvis
Frequent urination or difficulty fully emptying the bladder
Constipation or pressure on the rectum
Lower back pain or pain that radiates to the legs
Abdominal bloating significant enough to affect clothing fit or be visible
Painful periods (dysmenorrhea) are common but not universal. Some people with significant fibroids have surprisingly little pain.
What to Track
Fibroid-related symptoms are among the most useful to document carefully because the severity of symptoms, not simply the presence of fibroids, drives treatment decisions.
Menstrual Flow
The most objective way to track heavy bleeding is to log:
Products used per day: how many pads, tampons, cups, or discs, and whether they are regular or super absorbency
Saturation at change: was the product fully soaked or partially used
Clots: presence, approximate size (small/large, under or over a quarter)
Days of heavy flow vs. moderate vs. light
This gives a healthcare provider an actual estimate of blood loss rather than a vague description.
Period Duration
Log the start and end date of each period. If you define "end" as the last day of any flow including spotting, use that consistently.
Pelvic Symptoms
Rate daily pelvic discomfort on a consistent scale (0 to 10). Note location, type (pressure vs. cramping vs. sharp), and anything that makes it better or worse. Log bladder and bowel symptoms separately.
Functional Impact
Fibroids affect daily life in ways that matter clinically. Note days when you had to change plans because of bleeding or pain, missed work or other obligations, or avoided activities. Functional impact data is used in treatment conversations and can support accommodation requests.
Privacy and Fibroid Data
Fibroid-related tracking includes menstrual flow details, pelvic pain records, and potentially fertility-related data, all of which constitute sensitive health information. Period tracking apps that store data in the cloud can share this with advertisers or produce it in response to legal compulsion.
Flo Health settled a 2021 FTC enforcement action for sharing user period and health data with Facebook and Google, despite promising users their data was private. A $59.5 million class action settlement followed in 2025. Period tracking data is not covered by HIPAA and can be subpoenaed in any state.
An on-device tracker like Floriva keeps your logs on your phone exclusively. The company cannot access them, and they cannot be obtained remotely by third parties.
When to See a Healthcare Provider
See a healthcare provider if you experience:
Periods that are heavy enough to require changing protection every one to two hours
Periods that last longer than seven days
Clots larger than a quarter during menstruation
Pelvic pressure, bloating, or pain that is interfering with daily activities
Fatigue or dizziness that may indicate anemia from blood loss
Bladder or bowel symptoms associated with cycle changes
Unexpected bleeding outside of your expected period
Difficulty conceiving if you know or suspect you have fibroids
A pelvic ultrasound is the standard first step in evaluation. Bring several months of bleeding logs to the appointment. The more specific your records, the more useful the visit will be.
Definitions
- Uterine fibroid (leiomyoma)
- A noncancerous tumor composed of smooth muscle and connective tissue that grows within or on the uterus. Fibroids are extremely common. Many people have them without knowing it. They range from microscopic to several centimeters in diameter, and symptoms depend heavily on their size and where in the uterine wall they develop.
- Submucosal fibroid
- A fibroid that grows into the uterine cavity (the endometrial space). Submucosal fibroids are the most likely type to cause heavy menstrual bleeding and irregular cycles because they affect the surface area of the uterine lining. Even small submucosal fibroids can cause significant symptoms.
- Intramural fibroid
- The most common type of fibroid, which grows within the muscular wall of the uterus. Intramural fibroids can cause heavy periods, pelvic pressure, and an enlarged uterus depending on their size. Smaller intramural fibroids may be asymptomatic.
- Subserosal fibroid
- A fibroid that grows on the outer surface of the uterus. Subserosal fibroids are less likely to affect menstrual bleeding but can cause pelvic pressure, back pain, and bladder or bowel symptoms as they press on adjacent structures.
- Menorrhagia
- Abnormally heavy or prolonged menstrual bleeding. Clinically defined as blood loss exceeding 80 ml per cycle. In practice, it is identified by the need to change period protection every one to two hours, soaking through clothing or bedding, or passing clots larger than a quarter. Menorrhagia is the most common symptom of uterine fibroids.
Quick answers to the obvious questions.
What do fibroids feel like?
Many fibroids cause no symptoms at all and are found incidentally on imaging. When symptoms occur, the most common is heavy menstrual bleeding, often with clots. Other symptoms include pelvic pressure or a sense of fullness, a feeling of the abdomen being larger than expected, frequent urination (if the fibroid presses on the bladder), constipation or a sense of rectal pressure (if the fibroid presses on the bowel), and lower back pain. Pain is not always present, but period cramps can be more severe than usual.
Can fibroids cause bleeding between periods?
Yes, particularly submucosal fibroids. They can distort the uterine cavity and disrupt the normal hormonal regulation of the endometrial lining, producing spotting or irregular bleeding outside of the expected period. If you are experiencing regular intermenstrual bleeding, imaging to evaluate for fibroids or polyps is appropriate.
How does a doctor diagnose fibroids?
Fibroids are most commonly identified through pelvic ultrasound, which can reveal their size, number, and location. Transvaginal ultrasound often provides better resolution than abdominal ultrasound for smaller fibroids. In some cases, an MRI is used to map fibroids more precisely before treatment. A pelvic exam may detect an enlarged or irregularly shaped uterus, but cannot identify individual fibroids.
Do fibroids cause infertility?
Fibroids can affect fertility depending on their location. Submucosal fibroids that distort the uterine cavity have the clearest evidence of affecting implantation and pregnancy rates. Large intramural fibroids may also play a role. Many people with fibroids conceive without difficulty. If fertility is a concern, evaluation by a reproductive specialist who can assess fibroid location relative to the uterine cavity is recommended.
Questions people ask before they switch.
Do fibroids go away on their own?
Not typically during the reproductive years. Fibroids are estrogen-sensitive; they often grow during times of higher estrogen (reproductive years, pregnancy) and tend to shrink after menopause when estrogen falls. They do not usually disappear without treatment, but many remain stable or grow slowly and cause minimal symptoms for years.
What treatment options exist for fibroids?
Options range from watchful waiting for asymptomatic fibroids to hormonal medications (to manage bleeding and shrink fibroids temporarily), minimally invasive procedures (uterine fibroid embolization, focused ultrasound ablation), and surgical options (myomectomy to remove fibroids while preserving the uterus, hysterectomy as a definitive treatment). The right approach depends on fibroid size, location, symptoms, and fertility plans.
Is fibroid data sensitive from a privacy standpoint?
Yes. A detailed record of heavy bleeding, pelvic pain, fertility concerns, and treatment decisions is sensitive health information. Cloud-based period trackers can share this data with advertisers or third parties and may be compelled to produce it under legal process. On-device storage keeps this data off company servers entirely.