Nocturnal penile tumescence

Explores nocturnal penile tumescence (NPT), the spontaneous erections that occur during sleep, and what it reveals about vascular health, hormonal status, and erectile function. Understanding NPT can help men and their physicians distinguish between physical and psychological causes of erectile dysfunction.

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The essentials for nocturnal penile tumescence — then explore the latest posts below.

Why no morning wood happens and what it reveals about your vascular health

Why no morning wood happens and what it reveals about your vascular health

Dr. Alexander Grant, MD, PhD avatar
Dr. Alexander Grant, MD, PhD: Urologist & Men's Health Advocate
Dec 01, 2025 · 14 min read

Losing morning erections for many weeks often means nocturnal penile tumescence is being blunted by reduced penile blood flow, impaired nerve signaling, or poor sleep. This can flag vascular problems even when testosterone is normal. Here’s how to interpret the change and when it should prompt a closer look at diabetes and cardiovascular risk. “Morning ...

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