# The eXtroardinarY Babies Study: Natural History of Health and Neurodevelopment in Infants and Young Children With Sex Chromosome Trisomy

> **NCT03396562** · — · RECRUITING · sponsor: **University of Colorado, Denver** · enrollment: 300 (estimated)

## Conditions studied

- Klinefelter Syndrome
- Trisomy X
- XYY Syndrome
- XXXY and XXXXY Syndrome
- Xxyy Syndrome
- Xyyy Syndrome
- Xxxx Syndrome
- Xxxxx Syndrome
- Xxxyy Syndrome
- Xxyyy Syndrome
- Xyyyy Syndrome
- Male With Sex Chromosome Mosaicism

## Interventions

- **OTHER:** Assessments of Development and Growth

## Key facts

- **NCT ID:** NCT03396562
- **Lead sponsor:** University of Colorado, Denver
- **Sponsor class:** OTHER
- **Phase:** —
- **Study type:** OBSERVATIONAL
- **Status:** RECRUITING
- **Start date:** 2017-09-29
- **Primary completion:** 2028-03-01
- **Final completion:** 2028-03-01
- **Target enrollment:** 300 (ESTIMATED)
- **Last updated:** 2024-05-09


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03396562

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03396562, "The eXtroardinarY Babies Study: Natural History of Health and Neurodevelopment in Infants and Young Children With Sex Chromosome Trisomy". Retrieved via AI Analytics 2026-06-25 from https://api.ai-analytics.org/clinical/NCT03396562. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*