I didn’t find out with any of mine because it didn’t actually matter.
All the clothes I bought for DS1 were brightly coloured or neutral (red, orange, multi coloured zoo animals, black and white zebra/cow print, brown teddy bear fleece with ears etc ), and all 3 of them wore them.
Their rooms were decorated similarly in bright colours - zoo animals, koi fish in red/white/orange/black on pale blue, or black and white patterns with red accents, so totally suited to either sex.
Funnily enough as soon as DD was born (and we were inundated with pale pink stuff!) everyone said how happy we must be to have a girl after two boys. I’d have been perfectly happy with 3 boys tbh. They’re all unique and different, none of them conforming to the norms - gender or otherwise - in any way! Obviously during her nursery days DD loved dressing up in the princess dresses (as did a couple of the boys in her group) and she would choose the pink version of anything where there was an option, but I’m not daft enough to think I can hold back the pink tide with a single hand. It’s everywhere.
I honestly can’t understand why anyone would experience “gender disappointment”, as what sex a baby is has so little to do with anything these days. I can imagine that back in the days of Downton when it meant you wouldn’t inherit your family’s estate then it might be an issue, but really what bloody difference does it make?! My most cuddly and loving child is a boy. The one who takes the longest to get ready and is particular about their hair is a boy. The one with the most aggression - actually that’s a toss up between DD and DS1! I don’t really know much about the so called differences between boys and girls because it’s just not my experience of them. And they all still wear hand me down clothes with the same band-t shirts and jeans working their way down the family.
The only difference in the lives that lay ahead of them is that one of them may have to factor in having babies and the impact that has on her career path, so she has been taught from a young age about the importance of bearing that in mind, but thats the last thing I’d have thought about when I was pregnant.
Otherwise I can’t see what a sex/gender scan could have told me about them - other than using the word son or daughter when I talked about them, instead of Tiny or Baby.
Given that none of them even had a name until a week after they were born, as I wanted to wait and see what they felt like, it wouldn’t have even helped me there!