Otago has the lowest birth rate in the country, while Northland has the highest.

The national average is just over two children per woman, but Otago females only average 1.6.

It's believed that has a lot to do with the university population in Dunedin.

Statisticians say the large number of female students in the city tend to delay motherhood until they've completed their qualifications.

And around that time they typically move elsewhere.

The latest data has come from the 2013 census.

Otago's birth rate has been consistently low over the years.