By Kate Ryan

NEW YORK, June 13 (Thomson Reuters Foundation) — Some of the wealthiest nations in the world provide little or no government-supported maternity or paternity leave for new parents, a United Nations report said on Thursday.

Using 2016 data from the Organisation for Economic Co-operation and Development (OECD), Eurostat and research articles, the study ranked 41 high- and middle- income countries across the OECD and European Union on family friendly practices.

"All of these countries are rich compared to the rest of the world, so all of them can afford to invest in children and family-friendly policies," said Yekaterina Chzhen, lead author of the report by the United Nations children's fund UNICEF.

"Some of them could perhaps be more effective and efficient in spending money in this area," she told the Thomson Reuters Foundation.

Paid leave for mothers allows them to focus on their child's development while staying connected to their jobs, while paternity leave helps fathers bond with their children and balance the domestic weight placed on mothers, the report said.

Of the 41 countries surveyed, about half offered six months or more paid leave for mothers, the minimum length UNICEF advocated for in the report.

Estonia offered mothers 85 weeks of paid leave, Hungary offered 72 weeks, and Bulgaria offered 65 weeks, ranking as the top three countries for maternity leave.

But Australia and New Zealand offered only eight weeks and the United States offered no time, ranking it the worst for maternity leave.

When the data was collected, Estonia's gross domestic product, or the total value of its goods and services produced that year, was just below $24 billion, 750 times less than the United States.

"[There is] no relationship between country wealth and family friendliness of the policies in this particular group of UN-OECD countries," said Chzhen.

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"They depend a lot on, not just the political priorities of a particular day or a particular government administration, but they really sometimes build on how society views children and women."

Chzhen said she was surprised at the generous paternity leave for fathers in Japan and South Korea, which offer about 30 weeks and 17 weeks, while nine countries including the US, Israel, Ireland, and Switzerland offer none.

However, the report found that only one in 20 fathers in Japan actually took the paid leave in 2017.

Brian Heilman, a researcher at Promundo, a US-based organization trying to engage men and boys more in promoting gender equality, said there needed to be a shift in norms that may take years before better paternal leave policies take hold.

"You see a persistent gendered labour division under the guise of biological differences," said Heilman, noting that offering women more leave than men can add to their workload and perpetuate traditional domestic norms.

"When we add up unpaid work responsibilities on top of paid work, there's no country in the world where men are doing as much as women."

Just over 60% of the countries surveyed offered paternity leave, though some countries increased this benefit after the data for the report by UNICEF's office of research was collected, including Spain, Ireland, and Canada.

The report found that leave for fathers was often shorter but paid more than maternity leave.

It did not address how government funded leave impacts same-sex couples, though Chzhen said she believes gay fathers face the greatest resistance securing government assistance, as they might have to prove their needs are that of a birth mother.

The 2018 Global Gender Gap Report, released by the World Economic Forum, estimates it will take 202 years for economic equality between men and women to be achieved.

(Reporting by Kate Ryan, Editing by Michael Taylor)