Boshi Kenko Techo (Maternal and Child Health Handbooks) have been around since shortly after the war as part of government efforts to curb infant mortality and offer basic parental guidance and record-keeping for mothers.

In part because of Japan's experience and assistance, other parts of the world are also giving such guidebooks a look.

And at home, they are playing pivotal roles in lawsuits filed by more than 400 people with hepatitis B who blame the government for causing their infections via shared needles in mass vaccination drives.