How long does it take for the uterus to develop completely?

This varies from person to person, and the uterus will always develop. There will be secondary sexual characteristics around puberty, which is what we usually call development.

In the non-pregnant state, the uterus is 5ml in volume, with a forward-leaning and inverted pear shape, 7-8CM in length, 4-5cm in width and 2-3cm in thickness.

Basically developed to this state, it is mature.

The uterus will develop again during pregnancy, of course, we usually don't say that.

So our daily development is from adolescence to maturity. It's been several years.