Perhaps a couple already has several children of one gender and would like to have another child, but would only consider doing so if the 50/50 odds could be shifted in favor of the other gender. This is sometimes referred to as “family balancing”. Or, perhaps a couple is seeking infertility treatment, already has one child, and would prefer that the next child is the opposite gender. This is quite common nowadays as families are smaller in size. Another couple may want to avoid passing one of the more than 500 gender-linked genetic diseases to their child, so they might consider using PGT for gender selection.