Today, assisted reproductive technology (ART) includes certain methods that allow us to select the gender of the baby-to-be. There exist different methods depending on the stage of embryo development at which they are performed. If it is done by sperm sorting, before fertilization, we talk about preconception methods.
If the embryos have already been created and it involves choosing their gender at that point, the process will be done after conception has taken place.
Finally, should the woman be already pregnant and decides to continue with the pregnancy or not according to the gender of the fetus, the selection is said to be done during pregnancy.