I can't speak for the U.S. specifically but according to the National Institutes of Health, Turner Syndrome effects 1 out of every 2,500 female live births worldwide. For more information about it,...
No, not normally. Here is an article that will help you more than i can: http://en.wikipedia.org/wiki/Turner_syndrome
45 chromosomes
Yes, only women are born with the TS.
1 in every 2000 to 2500 live female births have Turner syndrome.