Effect of having children on time spent working
How were women's work hours affected relative to their hours prior to maternity leave?
A fair fraction of women worked fewer hours once they returned to work, and the proportions were similar, whether it was the 1st or 2nd child (with a slightly smaller impact of the 2nd child).
Women on the tenure track were more likely to work fewer hours than before, likely a reduction from a very heavy workload to begin with.