If men menstruated...

There are 193 countries in the United Nations, and just a few do not mandate paid parental leave, including: New Guinea, Suriname, a few island nations in the South Pacific, and the U.S.

According to data from the Pew Research Center, the U.S. is the only country among 41 nations that does not have a mandated paid leave program for new parents. The 41 nations make up the members of the Organization for Economic Cooperation and Development (OECD) and the European Union (EU).

Of the 40 nations with mandatory paid leave, the shortest amount of paid leave required is about two months. On the other hand, the country of Estonia provides workers with more than a year and a half of paid leave after becoming new parents. The following countries provide more than a year of paid time off:

Bulgaria
Hungary
Japan
Lithuania
Austria
Slovakia
Latvia
Norway
Slovenia
Notably, the majority of mandatory paid leave in half of the 40 counties is maternity leave, but 34 of the counties also have paid leave specifically for fathers. The length of time for paid paternity leave varies greatly.

Texas A&M reports that there are more than 50 countries that provide six months or more of paid maternity leave.

In many counties, maternity leave is paid at the employee's regular salary, while other countries pay only a portion of the regular salary. But the OECD reports that a majority of the 40 developed countries pay new moms at least half of their salary while on leave.

Some developed countries such as France and the U.K. began creating or expanding paid maternity leave as far back as after World War II to encourage women to stay in the workforce.