There is strong reason to believe the lack of flexibility would hit women much stronger than men.

Census that shows 82.6% of custodial single parents are female in the United States. http://www.census.gov/prod/2009pubs/p60-237.pdf

Article summarizing studies that show that even in marriages that attempt to be egalitarian both spouses agree the female ends up taking on more of the household responsibilities. http://www.nytimes.com/2015/07/31/upshot/millennial-men-find...