Menarche used in a sentence

Menarche in a sentence as a noun

After being adopted, the girls reached menarche at the ages of 7 or 8.

And early menarche might arguably be associated with long-term health problems.

Why has educational attainment gone up and age at menarche gone down if there is selection pressure in the other direction?

The author looks at the relationship between fitness, educational attainment, and age at menarche.

Then adolescence hit coupled with menarche and amplified social pressure to 'fit in' which caused her sense of strong individualization to wane.

Oh yes. Age of menarche is boring on its own, but the BMI and cancer correlations are interesting from an r/k selection perspective, and the tissue enrichment is especially interesting - what's with that massive overrepresentation of nervous system...?