Gender selection is a very common technology used in US over 30+ years ago and it's very effective. My neighbor is a reproductive specialist, married a Chinese wife and he introduced his the technology to fertility centers around China. Look up "John Wilcox" in Google and you will find the information about him. I understand those centers in China just went public and my neighbor no longer needs to work because he became very rich. For those who want boys, they don't need to remarry 4 times.