I gave birth to my kids in 1989 and 1992 -- long before this nonsense. I found out the old-fashioned way -- when they were born!
I knew anyway. I was so confident that my first was a girl that I instructed my grandma to make the quilt pink, and I wasn't wrong. I knew my son was a boy, too. I am either psychic or lucky, take your pick. I was there when my grandchildren were born and that's when we all found out my daughter also had first a girl and then a boy. I would never want to know ahead of time. That's like peeking under the wrapping paper before Christmas.