The United States and New Guinea are the only two countries out of 170 that do not currently provide financial support during maternity leave, according to the United Nations.

Instead, the 25-year-old Family Medical Leave Act simply required employers with 50 or more workers to grant parents 12 weeks of leave annually to care for a new child -- but did not guarantee pay during that time.

While paid leave has consistently had the support of Democratic lawmakers, supportive Republicans were harder to come by.

Senate Minority Leader Chuck Schumer and Senate Democratic negotiators secured a tentative agreement for the National Defense Authorization Act to include a significant provision requiring 12 weeks of paid parental leave for all federal employees. A Republican source confirmed that paid leave would be included in the bill.

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