We already ultrasound babies in the womb, so one would hope this has been studied.

Before ultrasound, they used to x-ray pregnant women to see the fetus. At that time, someone might have said "one would hope this has been studied"... unfortunately that practice went on for about 60 years before being stopped in the late 1950s.

Side note: kinda crazy they had medical x-rays in the 1890s. X-Ray imaging was discovered in 1985 and used clinically within 2 years.

But I do agree with your point, these days, I hope we're better about studying the potential dangers of current technologies we use.

We also used to x-ray people for shoe fitting/for lulz.

https://en.wikipedia.org/wiki/Shoe-fitting_fluoroscope

We also put lead in paint and gas because why the fuck not? Asbestos pretty much everywhere because it was a miracle material, etc. for decades, and we're still paying the price

> But I do agree with your point, these days, I hope we're better about studying the potential dangers of current technologies we use.

Sorry, but this is just pure "Gell-Mann amnesia effect" vibe to me. I mean, you've just brought up a perfect example yourself! What kind of mental gymnastics does it take to still hope that this time it's not like that?

I don't wanna start the whole "vaccines cause autism" thing and whatnot, and surely you shouldn't avoid ultrasound just because of irrational fear of some yet undiscovered side-effects, but it's really amazing, how people tell fun stories about how common was the narrative about major war being very unlikely in "modern days" (because who would dare to do that with this kind of technology!) right before WW1, and then conclude with firmly believing that these days (after WW2) it sure won't happen, because humans are not that dumb. And my point is, that perhaps it indeed might have been a bit less likely, if people didn't believe that it is so unlikely to keep stepping on the same rake.