If preimplantation genetic diagnosis is not done, the only option left would be fetal or prenatal resting through amniocentesis or chorionic villus sampling (CVS). The main disadvantage of this type of genetic testing is that the woman would have no alternative but to choose to terminate her pregnancy in case a genetic disease was detected, given that she has to be already pregnant for these techniques to be carried out.
Alternatively, prospective parents can decide not to use their oocytes and/or sperms to avoid the transmission of genetic diseases to their offspring. In such case, donor gametes would be used.
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