Squamous epithelial cells in urine almost always come from the skin around the genitals, not from inside the urinary tract itself. Their presence on a lab report typically signals that the urine sample was contaminated during collection, meaning skin cells got mixed in with the urine before it reached the cup. In most cases, this is not a sign of disease.
Why These Cells Show Up
Squamous epithelial cells are flat, scale-like cells that line the outer surfaces of the body, including the skin of the genital area, the vaginal walls, and the outer portion of the urethra. They shed constantly, the way skin cells do everywhere else on your body. When you collect a urine sample, these shed cells can easily wash into the cup if the surrounding skin hasn’t been cleaned thoroughly first.
The most common reason for finding squamous epithelial cells in urine is incomplete cleaning before a “clean catch” urine collection. If cells from the labia, vaginal lining, or the tip of the penis mix into the sample, the lab will flag them. This doesn’t mean anything is wrong with your kidneys or bladder. It means the sample picked up cells from outside the urinary tract on their way into the cup.
Women tend to have higher counts of these cells in their urine samples than men, simply because the anatomy makes contamination more likely. The urethra sits close to the vaginal opening, and vaginal squamous cells shed readily. During pregnancy, increased vaginal discharge can make contamination even more common. Menstruation is another factor that raises the chance of outside cells entering the sample.
What It Means on Your Lab Report
Labs typically report squamous epithelial cells using terms like “few,” “moderate,” or “many,” or they count the number of cells visible per high-power field under the microscope. A small number, often described as fewer than 5 per high-power field, is generally considered normal or insignificant. Higher counts suggest the sample was contaminated and may not accurately reflect what’s happening inside the urinary tract.
When contamination is significant, it can interfere with the accuracy of the rest of the urinalysis. Bacteria from the skin may also wash into the sample alongside the squamous cells, potentially producing a false-positive result for a urinary tract infection. If your provider sees a high squamous cell count, they will often ask you to collect a new sample using a more careful technique rather than treating based on those results.
Three Types of Epithelial Cells in Urine
Not all epithelial cells in urine carry the same meaning. The urinary tract is lined by three distinct types, and each one points to a different location in the body:
- Squamous cells come from the outer genital skin, vaginal walls, or the very end of the urethra. They almost always indicate contamination, not disease.
- Transitional cells line the bladder, ureters, and the upper part of the urethra. A small number is normal, but elevated counts can suggest inflammation or, rarely, a bladder condition.
- Renal tubular cells come from the kidneys themselves. Finding these in urine is more concerning because it can point to kidney damage, infection, or reduced blood flow to the kidneys.
If your lab report specifically says “squamous” epithelial cells, that’s the least worrying of the three. It’s the renal tubular cells that raise red flags about kidney health.
Less Common Causes Beyond Contamination
While contamination accounts for the vast majority of cases, squamous epithelial cells can occasionally appear for other reasons. Vaginal infections, including bacterial vaginosis or yeast infections, increase the shedding of vaginal lining cells, which can then end up in a urine sample. Sexually transmitted infections that cause inflammation in the genital area may have a similar effect. In these situations, you would typically have other symptoms like unusual discharge, itching, or odor, and the squamous cells are a secondary finding rather than the main diagnostic clue.
Urethral irritation from catheters, frequent sexual activity, or chemical irritants like harsh soaps can also promote cell shedding around the urethra. Again, the squamous cells themselves are not the problem. They are a byproduct of whatever is irritating the tissue.
How to Collect a Clean Sample
The clean-catch midstream method is designed to minimize contamination. If your sample came back with elevated squamous cells and you need to repeat the test, these steps make a significant difference.
For women: sit with your legs apart and use two fingers to spread the labia. Wipe between the labia from front to back using the sterile wipes provided in the collection kit. Use a separate wipe for each pass. Start urinating into the toilet first, then move the cup into the stream to catch the midstream portion. Stop collecting before you finish. The first and last portions of the urine stream carry the most skin cells, so catching only the middle gives the cleanest sample.
For men: clean the tip of the penis with a sterile wipe. If uncircumcised, pull back the foreskin before cleaning. Urinate briefly into the toilet, then collect midstream urine in the cup.
For both: wash your hands before starting. Don’t touch the inside of the cup or lid. Ideally, collect the sample when urine has been sitting in your bladder for two to three hours so it’s concentrated enough to give accurate results. Screw the lid on tightly and deliver the sample to the lab as directed.
When the Finding Actually Matters
On its own, a squamous epithelial cell count is not a diagnosis of anything. It’s a quality indicator for the sample itself. If the count is high, your provider is more likely to question the reliability of other findings in the same urinalysis, like bacteria or white blood cells, than to conclude you have a medical condition based on the squamous cells alone.
The finding becomes relevant in context. If squamous cells appear alongside white blood cells, bacteria, and symptoms like burning or urgency, your provider may still treat a suspected urinary tract infection but could request a repeat sample or a catheterized specimen to confirm. If the squamous cells are the only unusual finding on the report and you feel fine, the most likely explanation is simply that some skin cells got into the cup.