One medical and ethical aspect of assisted reproduction that should be considered is to what extent singleton pregnancies achieved following these procedures have (or ave not) more risks than those conceived naturally. In an extensive meta-analysis that included 161,370 births following assisted procreation and 2,280,241 conceived naturally, the authors concluded that assisted reproduction risksART [assisted reproduction technology] singleton pregnancies are associated with higher risks of pregnancy-related complications and adverse pregnancy outcomes, compared with those conceived naturally”(Fertility and Sterility 105; 73-85,2016).