Ericsson is technique that tries to separate the faster-swimming, boy-producing sperm from the slower-swimming, girl-producing sperm. Sperm of the wanted gender get placed directly into the uterus through AI.
Ericsson is 78 to 85% effective when choosing boys and 73 to 75% percent when choosing girls.
This technique, which was discovered in the ’70s, tries to separate the boy and girl sperm by pouring a sperm sample on a gluey layer of fluid in a test tube. All sperm naturally swims down, while the boy-producing sperm usually swim faster and reach the bottom sooner.
Once the fast and slow swimmers are separated, you get inseminated with the sperm that will most likely generate the gender you want.