What are the ways to conceive a boy or girl? In different cultural contexts, the selection of the sex of a boy or a girl is crucial for some families. While science doesn\’t offer a completely reliable way to predict gender, people have tried a variety of methods to achieve this goal. In this article, we will introduce some of the more scientific and generally accepted gender prediction methods. Genetic Factors Many people believe that the gender of a boy or girl can be predicted by the gender of close relatives. This isn\’t always true, but the mother\’s genes do affect gender. Specifically, male sperm has two dyes, X and Y.