First of all, let me just say that I'm just posting these threads to encourage discussion. I don't know why I'm TG, and I don't really care. As an engineer, it's just logical to me to search for the root cause.
As we all know, XX chromosomes are girls and XY chromosomes are boys, But, there are more variations than XX and XY, like multiple X's or Y's. I think the one most of us have heard of is Klinefelter's which is XXY. This occurs in 1 of 500 births. There are also other triplet variations, plus some singlet variations with a missing sex chromosome (X).
I personally have something even weider. My cells are mosaiced, which means that not all of the cells have the same genetic makeup. Technically, I'm 96% XY and 4% XXY. This is not something that I learned in biology class. How do I know this? After having one normal baby, my wife and I started trying for baby number 2. The first miscarriage was just an oops. The doctor didn't suggest anything except to try again. After the second miscarriage 4 months later, we captured the fetal matter and had a genetic analysis performed. Turned out that the fetus was trisomy 21 (Down's Syndrome), and it naturally miscarried.
Then I got some genetic testing, where I found out that I was mosaiced. My wife was 37 at the time, so she was probably starting to run on empty. We ended up with 4 confirmed miscarriages over 2 years, and maybe a couple of early first trimester miscarriages when my wife ended up being two to 3 weeks late.
We never did have that second child. They don't call it the miracle of childbirth for nothing.