Brief report: autistic-like traits in childhood predict later age at menarche in girls.

Researchers tracked 213 neurotypical girls from . At age 2, parents filled out the Child Behavior Checklist. The team scored items that map onto autism traits.

Years later they asked the girls when their first period arrived. They compared girls with high versus low early autism scores.

Girls who scored high on autistic-like traits at age 2 got their first period about five months later than peers. The difference stayed after removing girls who later got an autism diagnosis.

The delay was small but clear: 12.9 years versus 12.5 years on average.

Mulder et al. (2020) seems to say the opposite. They found autistic girls start puberty earlier than neurotypical girls. The key difference: O et al. studied neurotypical kids with mild traits, while A et al. studied girls already diagnosed with ASD. Traits in typical kids and full ASD may ride on different biology.

Lyall et al. (2011) adds a parent view. Mothers who had their own first period before age 10 were slightly more likely to later have a child with ASD. Together the papers hint that both mom’s early puberty and daughter’s autistic traits link to autism risk, but in different generations.

Keintz et al. (2011) used the same trait-score method in adults and showed high traits predict less eye-contact. The approach—counting sub-threshold features—now shows it can also forecast physical growth.

If you work with young girls who show social-communication quirks, expect puberty talks to come a bit later. Build body-education lessons ahead of time so they are ready when biology catches up. Also, share the finding with parents: a small delay is normal and needs no treatment, just monitoring.