The average woman in Germany has 1.5 children, the highest rate since 1982, the German statistics office said on Monday.

"We observe the continuation of a positive development since 2012," the statistic office said.

In 2014, the birthrate stood at 1.47 children per woman.

The most populous country in the European Union, Germany has more than 81 million people but has one of the lowest birthrates in the world.

Germany's aging population and a birthrate below the replacement rate of 2.1 children per women has prompted concerns over the declining population's impact on the economy and social security.

To fill the gap, Germany has relied on importing workers and accepting migrants, including more than 800,000 asylum seekers who arrived in the country in 2015.

The statistics released on Monday show German women had 1.43 children on average in 2015, up slightly from 1.42 in 2014.

However, the birthrate non-German origin women increased from 1.86 to 1.95 children per woman from 2014 to 2015, thereby "contributing significantly to the increase in the combined birthrate of all women," the statistics office said.

The average age of women at first birth was on average 29 years and seven months, a second child by nearly 32 years old and a third child by around 33 years old.

The statistics apply to women between 15 and 49 years old.