The data reported by that study doesn't even support the hypothesis, both the hybrid and adjusted fertility rates of women with <12 and 12 years of schooling are shown to still be higher than those of women with college and advanced degrees. Unless I'm misinterpreting something all this suggests is that there's a partial reversal, not an upheaval, of one of the most widely studied trends in fertility worldwide. The study does point out that childcare costs have outstripped wages of women with a high school diploma or less education though, which is alarming.