MicroSort gender selection is a type of sperm washing procedure, and sperm that went through this process is suitable for use with intrauterine insemination or IVF. How does this work? Sperm that carry the Y chromosome have significantly more DNA than X-chromosome sperm, so the machine used can sort the sperm in a semen sample on the basis of this.
MicroSort results in sperm samples that have a much larger number of sperm with the chosen chromosome, but it can't filter sperm of the chromosome that is avoided out altogether. Normally, sperm samples are about 50-50 in terms of "boy sperm" and "girl sperm", and MicroSort increases the chances of having a child of the target gender immensely.
If you are having IUI to conceive, don't think you can "just throw MicroSort in there too", though the procedure is currently only available to couples who wish to avoid passing on gender-linked genetic diseases to their offspring. If you qualify for the procedure, and are in the United States, you can contact MicroSort gender selection to take part in their trials.
In the meantime, other people should keep in mind that sperm washing is very useful for other purposes; without it, IUI patients would have big problems with uterine cramps. The cervix usually filters prostaglandins out before they reach the uterus, but that part is skipped when sperm is injected directly into the uterus with IUI. Sperm washing also produces a healthier sperm sample. And there are even indications that men who are HIV positive could avoid passing the virus onto their partner, and still have biological kids, through sperm washing.