Gay couples can form a family and become parents through surrogacy. In the process, they may choose to both give a sperm sample to fertilize a donor's eggs. In this way, one part of the eggs would be fertilized with the sperm from one and the other with the sperm from the other.
From all the embryos obtained, both from one and the other, one or two would be selected, depending on their quality and whether they wanted a multiple pregnancy or not. The selected embryos are transferred to the pregnant woman to see if a pregnancy develops.
It should be noted that when this option is chosen to have biological children, it will not be known which member of the couple is the biological father.