Birth rate
As of 2017, Niger has the highest birth rate in the world with 49.443 per thousand people. 
Japan has one of the lowest birth rates in the world with 8 per thousand people.
While in Japan there are 126 million people and in Niger 21 million, both countries had around 1 million babies born in 2016.
Mother
The total fertility rate (TFR), that is, the number of children born per woman, differs greatly from country to country. The TFR in 2013 was estimated to be highest in Niger (7.03 children born per woman) and lowest in Singapore (0.79 children/woman).