They also , of course , can choose to do this outside the context of in vitro fertilization . So some people are now opting to have their sperm samples spun out in this way , separate out the sperm that give rise to male or female offspring and then to only use the fraction that they are interested in , right ? So if they want a boy , they'll use one fraction .
There are now emerging methods that people are using in order to separate out the sperm that will indeed give rise to a male offspring versus a female offspring . Now , this of course is done in the context of in vitro fertilization .
This is an emerging data set and this is largely happening in clinics outside of the United States . But there are some clinics that have figured out methods in which they can take a sperm sample and they can spin that sperm sample in a centrifuge at a rate that separates out the sperm into what are called different fractions . So for those of you done a little bit of biology with centrifuges when you spin any kind of substance that includes multiple things in it , of different weights , when you spin them , that things of different weights segregate out into different fractions along the depth of the tube .
And then you can take out one fraction or the next simply with a little pipette , you take out the top fraction , the middle fraction and so forth . And what these clinics have figured out is that if they spin the sperm sample at the correct spin rate that the sperm that will give rise to male offspring and the sperm that will give rise to female offspring segregate out into different fractions , allowing them to take each of those fractions separately and to apply them to eggs . If it's in vitro fertilization and give rise very reliably , certainly much more than chance to either male or female embryos .
And then those sperm either are allowed to compete for those eggs and fertilize those eggs and allow them to advance to um very early embryo stage before those embryos are frozen and eventually implanted into a woman in order to have them be carried to full term . Ideally , or there's a procedure in which specific sperm are selected because they have the best morphology , motility and so forth . And in a process called II IC si in which the sperm themselves are literally forced to fertilize that particular egg .