The report, released Wednesday in Washington, D.C., was based on research on 168 countries.
More than 160 countries offer guaranteed paid leave to women for childbirth, according to the study. The U.S. Family Medical Leave Act guarantees 12 weeks of unpaid leave to about half of all mothers and nothing for the rest, the study said.
The report, completed with support from the Ford Foundation, said 139 countries mandate paid sick leave, with 117 of them guaranteeing at least one week. The United States does not guarantee time off for illness.
"The United States trails enormously far behind the rest of the world when it comes to legislation to protect the health and welfare of working families," said Jody Heymann, a Harvard associate professor who led the study.
Forty-five countries, not including the United States, ensure that fathers either receive paid paternity leave or have a right to paid paternity leave, the study said.
The United States also is not among the 76 countries guaranteeing mothers a right to breast-feed while at work.
In a statement accompanying a news release on the report, John Sweeney, president of the AFL-CIO, said the report should be considered a call to action.
"Working families are deeply concerned about how to balance work and home, and this thorough study should raise alarm bells from coast to coast about how far our nation needs to come to meet their needs," Sweeney said.