One of the many ways in which humans' evolved characteristics clash with a fast-changing post-industrial society can be seen in the female egg.
Even before a woman passes the age of 30, the quality of the oocytes she carries begins a downturn in quality, making conception more difficult and chromosomal abnormalities more likely. And her eggs take a steep dive in quality as she nears 40 -- whether or not she has found a suitable mate, achieved career goals or completed her pre-family to-do list. Where as it also effect in male sperm quality, motility and Morpfological change of structure.