Spending time with a newborn can have a significant impact on both the parent and the infant, and yet many countries lack policies to encourage parents, and especially fathers, to take time off to care for a new child.

In fact, according to new data released by UNICEF and compiled by the World Policy Analysis Center (WPAC) nearly 90 million children under the age of 1 live in countries where fathers aren't entitled by law to any kind of paid paternity leave, including the United States. Typically, it's up to individual businesses to decide how much paid leave fathers receive in these countries.

"Positive and meaningful interaction with mothers and fathers from the very beginning helps to shape children's brain growth and development for life, making them healthier and happier, and increasing their ability to learn. It's all of our responsibility to enable them to fill this role," UNICEF Executive Director Henrietta Fore said in a statement.

A global issue

WAPC offered the data in an interactive map, which color codes countries based on how much leave they offer. You can compare that map with one that shows which countries offer leave benefits for mothers. Spoiler alert: Only eight countries have no paid leave laws for mothers, and they are Papua New Guinea, Suriname, five small Pacific Island states, including the Marshall Islands, and the U.S.

Users can also compare countries' policies regarding leave options for either parent in data tables, including whether or not countries have job protections or if paid leave is structured in a way that encourages fathers to actually take paternity leave. (To explore the data, click here, select "Gender" from the topics menu and then select "Work-family" from the sub-topics menu. Columns will appear in the table below those menus with headings regarding policies.)

A man pushes a stroller through Bratislava, Slovakia A man pushes a stroller through Bratislava in Slovakia, which offers new dads 14 weeks or more of paid paternity leave. (Photo: Andr_Bog/Shutterstock)

According to the Organisation for Economic Cooperation and Development (OCED), which is dedicated to policies that improve economic and social well-being, all 35 member countries except the U.S. offer paid maternity leave for at least 12 weeks and more than half offer paid paternity leave. More countries are also offering paid parental leave, which is a longer period of job-protected leave available to both parents.

According to a policy brief released by OECD in 2015, fathers are less likely to take leave than mothers. Mothers generally take all their maternity leave and often extend it by taking some additional parental leave. Fathers, on the other hand, account for less than one in five of the people taking parental leave. This number varies from country to country, as the OECD notes, with 40 percent of men in some Nordic countries and Portugal taking parental leave, while maybe one in 50 takes leave in Australia and Poland. Japan and Korea both offer a year's worth of paid leave to fathers, but according to the OECD, very few fathers take advantage of it.

In many cases, the question of taking leave is driven by financial reasons. Women in OECD-participating countries still experience a gender pay gap around an average of 15 percent, which means that it's more viable for fathers to continue working, especially if the paternity leave isn't paid.

Making paternity leave viable

A Japanese father carries his daughter in a Tokyo Park Fathers in Japan rarely take advantage of their country's generous paternity leave policy. (Photo: MAHATHIR MOHD YASIN/Shutterstock)

"To achieve gender equality both in the workplace and the home, it's essential for men to have an equal chance to be there with their newborn babies," Jody Heymann, founding director of WPAC told NPR.

The OECD has a few recommendations to achieve that.

1. Reserve some leave for fathers only. Given the pay gap as well as gender norms, mothers are expected to handle most of the child rearing, which is why sometimes companies allow paternity leave to be transferred from fathers to mothers. Some countries are preventing this from happening in several ways. So-called "daddy quotas" require fathers to use a certain percentage of their paid leave by making it non-transferable. Other countries offer bonus weeks of paid leave if a father uses a certain amount of parental leave to be home.

2. Make sure parental leave is well-paid. This goes back to the wage gap. Many OECD countries offer leave to fathers, but it isn't paid. Research has demonstrated men will take the leave as long as it pays at least half or more of normal earnings.

3. Work out flexible leave arrangements. If parents aren't willing or able to leave work completely, part-time arrangements can be a solution. This can minimize the financial hit the parents take can can help companies avoid hiring someone else to fill in while a parent is on leave. Partners can also "shift-share" this part-time leave, trading off time spent working and caring for the baby.