Definitely bring it up to your neurologist, and if not, your primary care doctor/GP, if it’s started after the IUD placement, it’s important to rule out/confirm its role in this.
Personally, I’ve been wetting myself since childhood mostly due to hyposensitivity in my sense of interoception. I can’t “tell” as well as others, for me it’s an autistic thing, and stress (including the ambient levels of being out the house) makes it worse, I’m often “deaf” to it. I manage this with going to the bathroom routinely (eg. before I go out, periodically while I’m out, if possible, regardless of if I think I need it or not.) and I also use pads (urinary specific) when going out. I understand this is probably a very off-putting suggestion, but may be worth looking into in the meantime of this being addressed. I find being left to wet myself dehumanising, like they let happen at school. It’s given me some of my autonomy and dignity back, and I’ve learnt to accept it as a neutral part of life with the disability that I have, it’s also not common I actually have accidents nowadays, since I am not under as constant, overbearing pressure from my trauma and relating mental illnesses, which are in management, now; my sensory ear is a lot less overwhelmed ‘n’ overcrowded. Sometimes it just happens, or my body jumps the gun, but it’s not the end of the world anymore. I sort myself out, make note of if it was avoidable, carry on. I’m also trying to address engrained wounds, like finding the bathroom very vulnerable feeling and putting off going because of it (often hijacks my system of preventative measures).
Also bringing a change of clothes, I have a backpack and that’s one of the things I keep, for emergencies. I only have one pair of pants, but I keep an underwear and spare pad.
How you’ll need to address it will depend on the underlying cause of the incontinence (physical, mental, maybe both?). Which is why we advocate seeing the doctor and chasing the issue despite it being embarrassing. I could speculate that having the IUD and ultrasound may have jostled something trauma related. Bed wetting and dissociation is very common in CSA kids, may have stirred it back up due to the invasiveness of it. Also incontinence and dissociation can go hand in hand in trauma response territory (Polyvagal theory talks about it, I think). It is always good to check for/rule out physical causes, though, urogenital health is not something to mess around with or put to the side, unfortunately.