The asshole who wrote this is claiming that women who are voluntarily childfree are selfish losers. For some odd reason, the London School of Economics was doing this study. That doesn't make sense...
Satoshi Kanazawa says in his book that the desire to have children drops 25 percent for every 15 extra IQ points.
He had some strong words about childfree women:
If any value is deeply evolutionarily familiar, it is reproductive success. If any value is truly unnatural, if there is one thing that humans (and all other species in nature) are decisively not designed for, it is voluntary childlessness. All living organisms in nature, including humans, are evolutionarily designed to reproduce. Reproductive success is the ultimate end of all biological existence.
What about mental illnesses? Did he account for that, probably not?
We are not losers, we just want to control what happens to our bodies and our lives. We have an overpopulation problem anyway.