Mayor Kawata will take six weeks of leave before the birth and eight weeks after it, in line with the labour laws governing regular employees.
"In Japan, there is a deeply rooted pressure that the more senior you are, the less entitled you are to parental leave, creating a cycle where those at the top don't take it, so those below feel they cannot ask," Ms Konishi told the ABC.
"A mayor — someone in a role that is genuinely difficult to replace — demonstrating that an organisation can manage and adapt, sends a message that extends well beyond local government, into the private sector and society as a whole."