Some patients travel to America from abroad just for the procedure, as the U.S. is one of only a handful of countries that allows the process for non-medical reasons. There seems to be high interest in the process for some women living under one-child policies, especially if there is a cultural preference towards one gender or the other.
In one method, an embryo's chromosomes are tested to determine if it's male or female.
In Chrissy's case, she explained that she chose a girl, thinking that her husband John Legend would be the best father to a daughter. After undergoing in vitro fertilization, choosing the baby's sex didn't even register as all that unusual.
"What is that difference though?" the model tweeted. "I've already created embryos with a doctor. only after must it be random.This is all so interesting. I said it so casually because i'm just open. I'm around so many open-minded people & forgot it's controversial. anyhow I am not mad at anyone's beliefs but I don't really actively seek out people to make them feel bad about their decisions either."
The happy couple are expecting their first child this spring.