Most XO fetuses (Turner Syndrome) are miscarried or die before term, but the ones who do survive to birth have near-normal life expectancies, although they are usually very short, infertile, and have cosmetic differences, the most common being wing-like extra skin on the sides of their necks. Some of them also have heart defects and learning disabilities, although their average IQs are just slightly below normal. The one person I have met personally who has it also has significant hearing loss, although IDK if it's because of her Turner's Syndrome.
One of my FBFs is currently pregnant with a baby that may have it. Her last pregnancy ended in a stillbirth/miscarriage at about 18 weeks, when she got an infection and they determined his heart had stopped. They don't know why, because they did analyze his chromosomes and didn't find anything unusual. Like I told her, for some reason, he did everything he was supposed to do while he was here.
BTW, sex chromosomes can be in trisomy and the person may not know it until adulthood. Klinefelter Syndrome (XXY) is not an uncommon cause of male infertility, and is believed to be at least as common as Down Syndrome. Some scientists believed that XYY led to a tendency towards criminal behavior, but that has later proven to be untrue, although they do have a tendency towards aggression and severe acne, which may have led to that erroneous idea. Trisomy X (XXX) is also not incompatible with normal life, and when I read the description of its symptoms, it was like a big flashing beacon that a woman at my church who died a while back almost certainly had it. Infertility, taller than average, masculine facial features, large hands and feet - yep, that was her. She was about 6 feet tall and said she went through her "change" at age 21 (!) but she and her husband adopted two children, and she otherwise had a very normal life that ended when she was about 80 years old.
p.s. I vaguely remembered reading somewhere that among miscarried fetuses that have been studied, they've seen full trisomy of every chromosome excact #14. Even mosaics of trisomy 14 end very, very early, so that chromsome must have something REALLY nasty on it, or just plain old The Code For Life. Other people have been born with translocations (chromsomes that break off and swap places) and other anomalies, with varying degrees of disability.