The UTI Clinic

08/13/2026

08/12/2026

Did you know your bladder has a built-in defense against infection?

When the bladder wall encounters E. coli, it produces cathelicidin (LL-37) — a natural antimicrobial peptide that disrupts bacterial membranes before an infection can take hold. But there's a catch: your body needs enough vitamin D to ramp up LL-37 production. Vitamin D also helps strengthen the bladder lining itself, reinforcing the barrier against pathogenic bacteria.

In premenopausal women, low vitamin D (below 15 ng/mL) is linked to 4x higher odds of recurrent UTIs.

Here in the Pacific Northwest, low vitamin D is common thanks to our limited winter sun — and biology, digestive conditions, and restrictive diets can all play a role too.

The good news: a simple blood test tells you where you stand, and correcting a deficiency is straightforward.

If you're dealing with UTIs that keep coming back, vitamin D might be part of the picture. We'd love to help you figure out if it's part of yours.

www.theuticlinic.org

07/29/2026

We're doing a Reddit AMA — ask Dr. Posthuma anything about UTIs!

Standard urine culture and why it misses infections, modern testing, antibiotic alternatives, culture-negative symptoms that are still very real, estrogen and the bladder, root causes of UTIs.

📅 Live this Friday, 10am PT
⭐︎ RSVP now and drop your question early, we'll be answering it!

https://www.reddit.com/r/utis/s/d3j55DbsLR

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07/15/2026

07/15/2026

07/14/2026

Could hormones be causing your UTIs?

Your bladder has a built-in defense system, starting with the urothelium — the tissue that lines your bladder. Its outermost cells (called umbrella cells) are covered in a slippery, mucin-rich layer and bound together by tight junctions, forming a barrier that's nearly impenetrable to bacteria. This barrier protects you by:

⁕ Secreting natural antimicrobial peptides like cathelicidin (LL- 37) and defensins that kill bacteria
⁕ Expressing receptors that recognize bacteria and trigger an immune response
⁕ Shedding infected cells so they can be flushed out during urination

Estrogen plays a major behind-the-scenes role in keeping this whole system running:

⁕ Maintains a robust, hydrated mucin layer in the bladder
⁕ Feeds lactobacillus in the va**na, keeping things acidic and unfriendly to pathogenic bacteria
⁕ Upregulates cathelicidin (LL-37) to fight off bacterial growth
Regulates immune cell development and response

So when estrogen drops, this protective system can weaken — and that shows up in more ways than you might expect:

⁕ Menopause — levels start declining years before you might suspect
⁕ Breastfeeding — often mistaken for postpartum recovery or pelvic floor issues
⁕ Medications — birth control pills, endometriosis treatments, IVF meds, or fibroid treatments can all lower estrogen production
⁕ Restrictive diets or intense athletic training — even if your period is still present (just irregular)

If you've been dealing with recurrent UTIs, low estrogen could be part of the picture — and it's very treatable.

Wondering if va**nal estrogen is right for you? We can help.
www.theuticlinic.org

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07/13/2026

We don’t take insurance but probably not for the reason you’d guess.

07/08/2026

What if UTI care meant more than the standard urine culture and an antibiotic prescription?

We recently sat down with Live UTI Free, a patient advocacy and research organization, to talk about how we approach UTI care at The UTI Clinic. In this conversation, Dr. Leah Posthuma and PA Aubree Ng share why listening comes first, why your story matters just as much as your lab results, and how we're changing what UTI testing and treatment can look like.

If you've struggled with urinary tract infections — this one's for you. 🎥

👉 Watch "Beyond the Test Result": https://www.youtube.com/watch?v=FuKyHSKTBhU

Learn more about Live UTI Free's advocacy work: https://liveutifree.com/

Have questions about UTI care, or want to schedule with us? Send us a message or visit our website — we'd love to hear from you.

www.theuticlinic.org

In this video, Leah Posthuma and Aubree Ng discuss the following:...

05/28/2026

We're open for scheduling! We can't wait to meet you. Visit www.theuticlinic.org to learn more and book a consultation.