The Ericsson Method is an assisted reproductive technology for sex selection, used before implantation. In this method, sperm that will give rise to male versus female children are separated by moving at different speeds through a protein solution. When used to increase the likelihood of a female child, studies have resulted in between 70% and 80% female children. When used to increase the likelihood of a male child, studies have resulted in between 50% to 75% male children.