The key to determining the gender of the embryo is the 23rd pair of male sex chromosomes.

If the X-bearing sperm and the egg fuse, the sex chromosome in the fertilized egg is XX, which determine female gender of the newborn; On the other hand, if the Y-bearing sperm is fused with the egg, the sex chromosome in the fertilized egg is XY, which determine male gender of the newborn.

The question is, is there any way to select sperms with specific chromosomes?

There are two legendary techniques of semen segregation.

1.Density gradient: Use the physical difference that the Y chromosome is shorter and lighter than the X chromosome to make selections.

2.Swim-up: The selection depends on the better activity of sperm with Y chromosome than with X chromosome.

Actual processing of density gradient method: X and Y cannot be completely separated only by density!

Actual processing of swim-up method: Cannot effectively seperate sperm with different sex chromosomes.

Some people may ask: The third-generation IVF (PGS/PGT-A) is a chromosome screening technology. Can we know the gender if we do the third-generation IVF?

First of all, we should bear a correct concept in our mind:  PGS technology aims to avoid diseases with abnormal chromosome numbers in embryos and reduce the probability of miscarriage. Moreover, Article 16 of the Taiwan Artificial Reproduction Law clearly stipulates that gender selection is not allowed unless considering health factors.

In fact, boys and girls are both treasures. Growing up healthily is the most important!