According to the article you link to : (biologically the best age to have a baby is 19 because the...) "oocytes are fresh and the body’s reproductive and other systems are at a youthful peak"

I stopped reading after that. There's no such thing as 'fresh' oocytes. The author is just making stuff for his purpose as he goes along.

The ideal age for having kids lies somewhere in the range of late 20's to early 30's. Here both biological and sociological advantages convene.