If anyone is curious about the US, we are on average ~30:

https://www.nbcnews.com/news/motherhood-deferred-us-median-age-giving-birth-hits-30-rcna27827

Up from 27 not that long ago:

https://www.cdc.gov/nchs/products/databriefs/db232.htm

Like in Europe there are big gaps between areas (this is outdated but the geo-patterns are still probably relevant):

https://www.nytimes.com/interactive/2018/08/04/upshot/up-birth-age-gap.html

I always find things like this fascinating... I was exactly the average age of a first-time mother in my county, when I had my first child.