As soon as we figure out how to choose the sex of our children, we as a species are in serious trouble.
That's not the same as creating male embryos deliberately.
> A laminar-flow fractionation method, developed primarily for removing dead sperm from human semen, was successfully modified to enrich X and Y sperm to 80% purity, and to characterize each enriched fraction for individual swimming behavior. Y-sperm fractions were rapidly detected by fluorescent cytogenetic staining. Subsequently, the degree of enrichment was quantitated with DNA extracted from each sperm fraction probed with a human male-specific recombinant DNA clone. In stationary fluid, X and Y sperm swam in circles with the same average speed. However, in a flowstream, X sperm shifted to a nearly straight path of movement in a significantly decreased angular velocity. This shift was four times more pronounced in X sperm than in Y sperm, especially after the initial transition from stationary fluid to flow. The velocity gradient across the flow axis was essential for separating X and Y sperm; uniform flow velocity did not separate them effectively.
AMA Journal of Ethics - Sex Selection for Family Balancing https://journalofethics.ama-assn.org/article/sex-selection-f...
> Currently, there are three available methods for sex selection. The first option is prefertilization sperm sorting using flow cytometry, which can provide a semen sample enriched with sperm that bear the desired sex chromosome. Its accuracy is in the 84-92 percent range, and it is not yet available in the US [6, 7]. At the opposite end of the spectrum, the most extreme form of sex selection occurs after conception in the form of elective termination of pregnancy if prenatal testing shows the sex of the fetus is the opposite of that desired. In certain regions of the world, such as India, such procedures are commonly performed, despite being illegal [8, 9].