Most conversations about PE assume it's a fixed condition. You either have it or you don't. You always finish fast, or you don't have a problem.
That framing misses a large chunk of the men dealing with this. A study published in 2025 in the Journal of Integrative Neuroscience formally named what a lot of men already knew from experience: intermittent premature ejaculation, or IPE. The defining feature is inconsistency. Some nights you're in control. Other nights it's over in 60 seconds and you have no idea what happened differently.
This isn't a lesser version of PE. Research shows men with IPE share nearly all the same physiological markers as men with lifelong or acquired PE. The difference is in consistency of expression, not in the underlying system.
Understanding why your control fluctuates is more useful than accepting that "sometimes I'm fine."
What's Actually Varying Night to Night
Your ejaculatory threshold isn't fixed. It shifts based on a handful of variables that combine differently each time.
Nervous system state. This is probably the biggest one. Your sympathetic tone (the baseline activation level of your fight-or-flight system) varies considerably based on sleep quality, stress load, recent physical activity, and how you're feeling going into sex. On a night when you're genuinely relaxed, your baseline activation is lower, and you have more runway before stimulation tips you over the edge. On a stressed, underslept night, that runway shrinks dramatically.
Arousal context. How aroused you are before physical contact begins matters more than most men realize. If you've been thinking about sex for hours, watching porn earlier in the day, or just had a long dry spell, your arousal is pre-loaded. Your body is already part of the way there before anything physical happens. The stimulation during sex is then added on top of an already elevated baseline.
Pelvic floor state. Your pelvic floor muscles hold chronic tension that varies by day. After sitting at a desk for eight hours, your pelvic floor is likely more contracted than it should be. After a workout that included hip flexor stretches, it's probably more relaxed. These muscles are directly involved in the ejaculatory reflex. Their resting tension affects your threshold.
Alcohol. A lot of men notice they last longer after a drink or two. This is pharmacologically straightforward: alcohol is a nervous system depressant that lowers baseline sympathetic activation. The fact that it helps is useful diagnostic information (more on this below), but it's not a strategy.
Why Intermittent Is Actually Harder to Work With
Consistent PE is, in a strange way, easier to address. You know the problem is always there. You can build a systematic response to it.
Intermittent PE introduces a different psychological layer. The good nights give you false hope. "Maybe it's getting better." The bad nights hit harder because they're unexpected. And because the problem isn't constant, it's tempting to believe it'll just resolve on its own.
It rarely does without intervention. What's actually happening on the good nights isn't that the underlying system is fixed. It's that the conditions happened to line up favorably. The nervous system was calmer. Arousal wasn't pre-loaded. The pelvic floor was more relaxed. You got lucky with the variables.
The goal isn't to hope the variables align. It's to lower your resting baseline on all of them so that even unfavorable conditions don't push you over.
The Assessment Question That Matters
If your PE is intermittent, the first useful question is: what's different about the nights when you're in control?
Most men, when they think about it, can identify patterns. Better sleep the day before. Less stress. A longer warm-up. A couple of drinks. Not being overly excited going in. Sex happening spontaneously rather than being anticipated for hours.
These aren't random. They're pointing directly at which part of your system is the weak link. If sleep is the consistent differentiator, your nervous system hyperreactivity is the primary driver. If the warm-up length matters, your arousal awareness and pelvic floor tension are likely involved. If anticipation kills you, conditioned psychological response is in play.
Control: Last Longer's assessment is built to identify exactly this. Which of the six PE mechanisms are active for you, and to what degree, determines what your protocol should actually look like. For men with intermittent PE, the protocol is usually a combination of nervous system regulation (extended-exhale breathing, consistent edging practice) and pelvic floor work focused on reducing resting tension rather than building strength.
Consistency Is the Actual Training Target
Here's the reframe that helps: the nights when you're in control aren't proof that you don't have a problem. They're proof that your system can perform at a higher threshold, but only under specific conditions.
Training is the process of making those favorable conditions your baseline, not your lucky exception.
That means daily practice even when you're not having sex. Breathwork that builds your vagal tone so your nervous system's resting state is calmer. Pelvic floor stretching that lowers the chronic tension in those muscles. Edging practice that deliberately exposes your nervous system to high arousal and trains it to stay regulated.
The variability you experience now is actually useful information. It tells you the system is trainable, because it's already working sometimes. The gap between your best nights and your worst nights is the gap that training closes.
If the inconsistency has been the most frustrating part, that's the place to start.