White blood cells, also called leukocytes, are immune system cells that help your body fight infections, respond to inflammation, and protect against harmful invaders. They circulate in the blood and move into tissues when needed. In men’s health and fertility, white blood cells matter not only because they reflect overall immune activity, but also because abnormal white blood cell findings in blood, urine, or semen can point to infection, inflammation, or other medical issues that may affect general health, sexual health, and reproductive function.
At a glance: white blood cells are essential for defense, but too many, too few, or white blood cells showing up in the wrong place can signal a problem worth evaluating.
Key takeaways
- White blood cells are immune cells that help defend the body against infection and injury.
- A normal blood white blood cell count varies by lab, but many adults fall roughly in the range of 4,000 to 11,000 cells per microliter.
- High white blood cells can happen with infection, inflammation, stress, smoking, certain medications, or blood disorders.
- Low white blood cells can increase infection risk and may be linked to viral illness, medication effects, autoimmune disease, bone marrow problems, or nutrient deficiencies.
- In semen, excess white blood cells may suggest inflammation or infection and can be associated with oxidative stress that may affect sperm quality.
- An abnormal result does not diagnose a condition by itself; it needs context, symptoms, and often repeat testing.
- In men’s health, white blood cell findings may show up in blood tests, urine tests, or semen analysis.
- Persistent abnormalities, fever, recurrent infections, or fertility concerns warrant medical review.
What are white blood cells?
White blood cells are part of the body’s defense system. They are produced primarily in the bone marrow and circulate through the blood, lymphatic system, and tissues. Their job is to recognize threats such as bacteria, viruses, fungi, parasites, damaged cells, and foreign substances, then help contain or remove them.
Unlike red blood cells, which mainly carry oxygen, white blood cells are specialized for immune surveillance and response. They do not all do the same job. Different white blood cell types respond to different threats and phases of the immune process.
When people talk about a “white blood cell count,” they usually mean the total number of leukocytes measured on a complete blood count or CBC. But in practice, white blood cells are also relevant in:
- Urine tests, where they may suggest urinary tract inflammation or infection
- Semen analysis, where elevated white blood cells can reflect genital tract inflammation or infection
- Specific immune or hematology testing when a blood disorder or immune condition is suspected
Types of white blood cells
There are several major types of white blood cells, and each plays a distinct role. A white blood cell differential breaks the total count down into these categories.
| Type | Main role | Common associations when elevated or abnormal |
|---|---|---|
| Neutrophils | First-line defense against many bacterial infections; respond quickly to inflammation | Acute bacterial infection, inflammation, stress response, steroid use |
| Lymphocytes | Include B cells, T cells, and natural killer cells; key for viral defense and immune memory | Viral infections, immune disorders, some blood cancers |
| Monocytes | Help clean up damaged tissue and support longer-term immune responses | Chronic inflammation, recovery from infection, some autoimmune conditions |
| Eosinophils | Involved in allergic responses and defense against parasites | Allergies, asthma, parasitic infections, some drug reactions |
| Basophils | Participate in allergic and inflammatory signaling | Allergic states, chronic inflammation, certain blood disorders |
If your result shows only a total white blood cell count, you may need a differential to better understand which kind of immune response is happening.
Why white blood cells matter
White blood cells matter because they are one of the clearest windows into how the immune system is behaving at a given moment. They can rise when the body is fighting something off, fall when bone marrow production is impaired or immune cells are being depleted, and appear in body fluids where they are not normally expected when inflammation is present.
In real-world terms, white blood cells can help clinicians evaluate:
- Infections
- Inflammatory conditions
- Allergic reactions
- Medication effects
- Immune system disorders
- Bone marrow problems
- Certain cancers, especially blood cancers
- Fertility-related inflammation or genital tract infection
That said, white blood cells are not a diagnosis by themselves. They are an important clue that has to be interpreted in context.
Normal white blood cell ranges and what’s considered abnormal
Normal ranges vary slightly by laboratory, age, medical history, and the type of test being used. For many adults, a typical blood white blood cell count falls around 4.0 to 11.0 x 109/L, which is the same as roughly 4,000 to 11,000 cells per microliter.
What’s normal vs what’s not?
| Finding | General meaning | What it may suggest |
|---|---|---|
| Normal WBC count | Within the lab’s reference range | No obvious blood-count abnormality, though symptoms may still need evaluation |
| High WBC count (leukocytosis) | Above the reference range | Infection, inflammation, stress, smoking, medication effect, or less commonly a blood disorder |
| Low WBC count (leukopenia) | Below the reference range | Reduced immune defense, possible viral illness, medication effect, autoimmune disease, nutrient deficiency, or bone marrow issue |
| Elevated semen white blood cells (often called leukocytospermia or pyospermia) | Too many white blood cells in semen | Genital tract inflammation, infection, or oxidative stress affecting sperm function |
| White blood cells in urine | Inflammatory cells detected in urine | Urinary tract infection, irritation, stones, prostatitis, or contamination |
One key point: a mildly abnormal result may not mean anything serious, especially if it occurs during a short-term illness, after hard exercise, or during physiologic stress. Persistent or significantly abnormal results deserve more attention.
What causes high white blood cells?
A high white blood cell count is called leukocytosis. It often means the immune system is activated, but the reason can range from routine to serious.
Common causes of high white blood cells
- Infections, especially bacterial infections
- Inflammation from injury, autoimmune disease, or inflammatory conditions
- Physical or emotional stress, including surgery, trauma, or severe illness
- Smoking
- Certain medications, such as corticosteroids
- Allergies or asthma, especially when eosinophils are elevated
- Dehydration, which can concentrate blood components
- Blood and bone marrow disorders, including leukemia or myeloproliferative conditions
When high white blood cells may be less concerning
A temporary rise may happen during:
- Acute infection or recovery from infection
- Intense exercise
- Poor sleep or major stress
- Use of certain medications
When high white blood cells may need urgent evaluation
Very high counts, especially with symptoms such as fever, night sweats, unexplained weight loss, enlarged lymph nodes, easy bruising, or fatigue, may need prompt medical assessment.
What causes low white blood cells?
A low white blood cell count is called leukopenia. Depending on which cell line is low, it can reduce the body’s ability to fight infection. Low neutrophils, specifically, are called neutropenia and can be especially important because neutrophils are critical for bacterial defense.
Common causes of low white blood cells
- Viral infections
- Medication side effects, including some antibiotics, antithyroid drugs, immunosuppressants, chemotherapy, and others
- Autoimmune disease
- Bone marrow suppression or damage
- Nutritional deficiencies, such as vitamin B12, folate, or sometimes copper deficiency
- Alcohol misuse
- Some inherited conditions
- Enlarged spleen, which can trap blood cells
Low white blood cells are not always dangerous, but if they are significantly low or persistent, the infection risk may rise. This is especially important if the reader has frequent fevers, mouth sores, recurrent skin infections, or is taking medications that affect the immune system.
Symptoms and signs linked to abnormal white blood cells
Abnormal white blood cell counts often do not cause symptoms on their own. Symptoms usually come from the underlying cause.
Possible symptoms when white blood cells are high
- Fever or chills
- Signs of infection such as sore throat, cough, burning with urination, or skin redness
- Fatigue
- Body aches
- Swollen lymph nodes
- Inflammatory symptoms such as joint pain or swelling
Possible symptoms when white blood cells are low
- Frequent infections
- Fever
- Mouth ulcers
- Recurrent sinus or chest infections
- Skin infections
- Unusual fatigue during illness
Possible symptoms when white blood cells are elevated in semen or the genital tract
- Sometimes no symptoms at all
- Painful ejaculation
- Pelvic or perineal discomfort
- Urinary burning or urgency
- Pain, swelling, or discomfort in the testicles or epididymis
- Abnormal semen analysis or unexplained fertility issues
How white blood cells are tested
The most common test is a complete blood count (CBC). If a result is abnormal, the next step is often a CBC with differential, which shows the proportion and number of each white blood cell type.
Common tests involving white blood cells
- CBC – measures total white blood cell count, red blood cells, hemoglobin, hematocrit, and platelets.
- CBC with differential – breaks white blood cells into neutrophils, lymphocytes, monocytes, eosinophils, and basophils.
- Peripheral blood smear – looks at blood cells under a microscope to evaluate shape, maturity, and abnormal patterns.
- Urinalysis – can detect white blood cells in urine, often a sign of inflammation or infection in the urinary tract.
- Semen analysis – may identify white blood cells in semen, especially when fertility or genital tract inflammation is being investigated.
- Culture or infection testing – used if infection is suspected.
- Further hematology testing – used when a blood or bone marrow disorder is a concern.
How doctors interpret an abnormal result
Interpretation usually depends on:
- How high or low the count is
- Which white blood cell type is affected
- Whether symptoms are present
- Whether the abnormality is new or longstanding
- Medication use
- Recent infection, surgery, stress, sexual health symptoms, or fertility concerns
What white blood cells mean in men’s health and fertility
In men’s health, white blood cells can be relevant in several ways. A routine blood test may identify an immune or inflammatory issue. A urine test may suggest prostatitis, urethritis, or urinary tract inflammation. A semen analysis may detect excess white blood cells that could affect reproductive potential.
For fertility, the key issue is often not the white blood cells themselves, but what they may indicate:
- Genital tract infection
- Inflammation of the prostate, epididymis, or accessory glands
- Oxidative stress that may damage sperm membranes or DNA
- Possible effects on sperm motility, morphology, or function
Not every man with white blood cells in semen is infertile, and not every abnormal semen result is caused by inflammation. But this is a meaningful part of the evaluation when a couple is trying to conceive or when semen results are otherwise abnormal.
White blood cells in semen: why they matter
White blood cells in semen are often discussed using the terms leukocytospermia or pyospermia. This generally means semen contains a higher-than-expected number of white blood cells, often defined by laboratory standards as more than 1 million white blood cells per milliliter of semen.
These cells may increase because of infection, inflammation, oxidative stress, or trauma to the male reproductive tract. In some men, no clear cause is found.
How excess white blood cells may affect sperm
- They can release reactive oxygen species, which may increase oxidative stress.
- Oxidative stress may impair sperm motility, reducing how well sperm swim.
- It may affect sperm membrane integrity.
- It may be associated with sperm DNA damage in some cases.
- It can point to an underlying condition that itself hurts fertility.
Possible causes of white blood cells in semen
- Prostatitis
- Sexually transmitted infections
- Urethritis
- Epididymitis
- Accessory gland inflammation
- Recent fever or infection
- Smoking and oxidative stress-related exposures
- Varicocele in some cases
- Sometimes no identifiable cause
Important nuance
Round cells seen on semen analysis are not always white blood cells. Some may be immature germ cells. That is why specialized testing or staining may be needed to confirm whether the cells are truly leukocytes.
| Finding on semen analysis | What it may mean | Why follow-up may be needed |
|---|---|---|
| Normal or low white blood cells | No clear sign of inflammatory leukocyte excess | Fertility issues may still have other causes |
| Elevated round cells | Could be white blood cells or immature sperm cells | May need special testing to distinguish the two |
| Confirmed leukocytospermia | Excess white blood cells in semen | May prompt evaluation for infection, inflammation, oxidative stress, and sperm impact |
Treatment and management
There is no single treatment for abnormal white blood cells because treatment depends on the underlying cause.
If white blood cells are high in blood
Management may include:
- Treating an infection if one is present
- Reviewing medications that may be pushing the count up
- Repeating the CBC to see if the change is temporary
- Evaluating for inflammatory, autoimmune, or hematologic conditions when appropriate
If white blood cells are low in blood
Management may include:
- Checking for medication side effects
- Looking for vitamin or nutrient deficiency
- Testing for viral infections or autoimmune disease
- Considering hematology referral if the count is significantly low or persistent
- Monitoring more closely when infection risk is elevated
If white blood cells are present in urine
Treatment depends on the cause and may involve antibiotics if there is a bacterial urinary infection, but it may also require evaluation for stones, prostatitis, irritation, or noninfectious inflammation.
If white blood cells are elevated in semen
Possible next steps may include:
- Repeat semen analysis if needed, because semen parameters can fluctuate.
- Confirm whether round cells are true white blood cells.
- Assess for symptoms of prostatitis, STI exposure, urinary symptoms, or pelvic discomfort.
- Consider semen culture or STI testing in selected cases.
- Treat a confirmed infection when present.
- Address lifestyle factors that may increase inflammation or oxidative stress.
- Consider referral to a urologist or male fertility specialist if fertility is affected.
Can you lower white blood cells naturally?
If the issue is mild and due to reversible inflammation or lifestyle factors, addressing the underlying trigger may help. Depending on the situation, that may include:
- Stopping smoking
- Improving sleep
- Managing stress
- Working toward a healthier weight
- Reducing heavy alcohol use
- Getting appropriate treatment for infection instead of ignoring symptoms
- Following a diet pattern that supports overall metabolic and inflammatory health
Still, “natural” approaches should not replace medical evaluation when results are significantly abnormal or symptoms are present.
When to see a doctor
You should seek medical advice if:
- Your white blood cell count is repeatedly high or low
- You have fever, chills, or signs of infection
- You get frequent infections
- You have unexplained weight loss, night sweats, or swollen lymph nodes
- You have urinary burning, pelvic pain, or testicular discomfort
- You have abnormal semen analysis findings or are struggling to conceive
- You are taking medications known to affect bone marrow or immune function
- You have a weakened immune system
Urgent evaluation is especially important for high fever, severe weakness, shortness of breath, confusion, or signs of serious infection.
Common myths about white blood cells
Myth: A high white blood cell count always means infection.
Reality: Infection is common, but inflammation, stress, smoking, medications, and blood disorders can also raise the count.
Myth: A normal white blood cell count means nothing is wrong.
Reality: You can still have symptoms, inflammation, or even certain infections with a normal total count.
Myth: White blood cells in semen automatically mean infertility.
Reality: They can be relevant, but they do not guarantee infertility. The significance depends on how elevated they are, whether infection is present, and what the rest of the semen analysis shows.
Myth: All round cells in semen are white blood cells.
Reality: Some round cells are immature sperm cells, which is why confirmatory testing can matter.
Myth: If white blood cells are slightly off, it must be serious.
Reality: Mild abnormalities are common and often temporary, but they should still be interpreted correctly.
Questions to ask your doctor
- Is my white blood cell count only slightly abnormal, or significantly out of range?
- Do I need a repeat CBC or a white blood cell differential?
- Could my medications, supplements, smoking, or recent illness explain this result?
- Should I be tested for infection, inflammation, or an autoimmune condition?
- If white blood cells were found in my urine or semen, what is the most likely cause?
- Could this affect fertility, sperm quality, or conception?
- Do I need a urologist, fertility specialist, or hematologist?
- What symptoms should prompt urgent follow-up?
Frequently asked questions
What is the normal white blood cell count?
For many adults, a typical blood white blood cell count is roughly 4,000 to 11,000 cells per microliter, though ranges vary by lab. Always interpret the result using the reference range on your report.
Does a high white blood cell count mean I have an infection?
Not always. Infection is one common cause, but stress, smoking, inflammation, medications, and some blood disorders can also raise white blood cells.
Is a low white blood cell count dangerous?
It can be, especially if it is significantly low or involves neutrophils. A low count may increase infection risk, but the importance depends on how low it is, how long it has been present, and whether symptoms are occurring.
What do white blood cells in semen mean?
They may suggest inflammation or infection in the male reproductive tract. In some cases, they are linked to oxidative stress that can affect sperm quality. Follow-up may be needed to confirm the finding and identify the cause.
Can white blood cells affect male fertility?
Yes, in some cases. Elevated white blood cells in semen may be associated with poorer sperm motility, oxidative stress, or sperm DNA damage. But not every case has a major fertility impact.
Can white blood cells in semen be treated?
Sometimes. If a specific infection or inflammatory cause is found, treatment may help. In other cases, doctors may recommend repeat testing, lifestyle changes, or specialist evaluation rather than automatic treatment.
Why would white blood cells be found in urine?
White blood cells in urine often suggest inflammation in the urinary tract. Causes include urinary tract infection, prostatitis, kidney stones, irritation, or contamination of the sample.
Can stress raise white blood cells?
Yes. Physical stress, intense exercise, surgery, illness, and sometimes emotional stress can temporarily increase white blood cell counts.
Should I worry about one abnormal white blood cell test?
Not necessarily. Many mild abnormalities are temporary. But if the result is significantly high or low, repeats over time, or comes with symptoms, it should be evaluated.
What specialist treats abnormal white blood cells?
That depends on the setting. A primary care clinician often starts the workup. You may then be referred to a hematologist for blood count issues or a urologist/male fertility specialist if the concern involves semen, the prostate, or reproductive health.
References
- MedlinePlus. Complete Blood Count (CBC).
- American Society of Hematology. Patient resources on blood counts and white blood cells.
- Merck Manual Professional Edition. Leukocytosis and leukopenia.
- Mayo Clinic. White blood cell count overview.
- World Health Organization. WHO Laboratory Manual for the Examination and Processing of Human Semen.
- American Urological Association and American Society for Reproductive Medicine guidance on male infertility evaluation.
- StatPearls. Leukocytospermia; Leukocytosis; Neutropenia.
- National Institutes of Health and National Library of Medicine resources on immune cells, semen analysis, and male reproductive tract inflammation.
