There are still plenty of moms and dads who "stay at home" for the sake of the family. Sometimes this is by choice, where the family is wealthy enough that one of the parents doesn't need to work. Sometimes, though, this is done out of necessity. Maybe the family is unable to pay the often-expensive rates for child care, or maybe one of the parents simply can't find a job.
In either case, the parent who stays at home -- which is often the mother -- is put in a difficult position. They are spending some of their best-earning years out of the work force. They are putting a huge employment gap in their resume. And when they do get a new job, their earning power is likely to be significantly decreased.
This is just another reason why prenuptial agreements are very important for marrying couples. Provisions can be inserted into the contract that help protect any spouse who becomes the "stay-at-home" parent to financially deal with the divorce and its aftermath. Alimony is a typical form of financial help given to a stay-at-home parent who is suddenly thrust into a position where he or she needs a job -- and fast -- in order to get by.
This matter becomes even more important when you consider a rising trend of stay-at-home moms in the last 15 years. According to the Pew Research Center, in 1999 the number of mothers who stayed at home with children under 18 hit an all-time low of 23 percent. But since then, the number has steadily climbed to today's rate of 29 percent.
Source: CNBC, "Stay-at-home moms are on the rise," Annalyn Kurtz, April 8, 2014