If fully synthetic people will be created in the far fututre and there will proibably exist many kinds of synthetic humans, what do you think that in there will exist a kind of artifitial people who would be all female and who would have CAIS(Complete Androgen Insensitivity Syndrome)?
CAIS is a genetic mutation that cause genetic receptors genes to fail and not work at all in embryos who have xy chromossomes caryotype. These people are female but are genetically male. They have female external genitalia but they don`t have wombs, don`t have ovaries, cervix nor eggs and therefore are sterile and cannot get pregnant and can`t have menopause as well. Their bodies turn testosterone into estrogen. They are like a kind of "natural" transexual but unlike male to female transexuals, people with CAIS are born women. That is why they are called often called the perfect woman.
Back to the main issue of the thread, synthetic humans will have no need to reproduce because they will be artifitial and there will exist the technology to created them like we have the technology to create computers today. So if all synthetics will be sterile(male synthetics included as well) there would be pretty good even if synthetics makeup a small percentage of the total population in the future.