Fathers-to-be learn to how to hold newborn babies in Handan hospital on June 15, 2014. [Photo/IC]

When Kensuke Miyazaki, a member of Japan's ruling Liberal Democratic Party in the lower house, applied for a one-month childcare leave in December, party heavyweights criticized him for "maligning the reputation of all Diet members". He is the first Japanese lawmaker to apply for paternity leave and advocate men's obligation to support women in looking after children. Miyazaki believes paternity leave will help arrest Japan's falling birthrate.

Indeed, figures show families in which fathers shoulder more household responsibilities tend to have more children.

Some senior LDP members say lawmakers, unlike private sector employees, should not be institutionally entitled to take childcare, or paternity, leave, because their salaries are paid by taxpayers.

Miyazaki, however, resigned in February for having an extramarital affair days before his wife Megumi Kaneko, also an LDP member in the lower house, gave birth to their first child.

Under Japanese law, male employees with young children are entitled to one-year childcare leave if they have worked for more than a year for the same employer. But official data show only 2.63 percent of Japanese men actually take paternity leave. The Japanese government has vowed to raise the figure to 13 percent by 2020.