Why? One possible reason: Better educated and wealthier women are more likely to conceive during heat waves, because they can more easily stay in comfortable places to copulate. "Sexual activity decreases in heat waves," the authors say, and, "those decreases are disproportionately large for lower income individuals." Another possible reason, the authors said, is that fetuses of the poor and uneducated might be less likely to survive in utero.
--Jon Hilsenrath, WSJ, on the quirky consequences of air conditioning