This observational study, called the eXtroardinarY Babies Study, is looking at the natural development and health of infants and young children with certain sex chromosome variations, such as Klinefelter Syndrome (XXY), Trisomy X (XXX), and XYY Syndrome. Researchers want to understand how these conditions affect development, health, and early hormone function. They will also evaluate different developmental screening tools to help pediatricians better care for children with these conditions. You might be able to join if you have an infant between 6 weeks and 13 months old with a prenatal diagnosis of a sex chromosome variation that is confirmed after birth, and you speak English or Spanish. The study will measure cognitive, motor, and language scores using the Bayley-III assessment at 36 months of age to understand developmental progress.

Study design

This is an observational study planning to enroll 300 participants. It is not testing a specific drug or treatment.

What's involved

Participants will have longitudinal observational assessments of development and growth at various ages, from 2 months up to 9 years old.

Compensation

Not stated in the trial record.

Follow-up

Participants will be followed until at least 9 years of age, with primary endpoints measured at 36 months.

AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.