Clinical features: Most commonly girls with triple X syndrome have no altered physical features or medical problems. They can, however, be taller than average and have an increased risk of mild learning disabilities, particularly speech delay. These characteristics do vary enormously amongst affected females. The majority of women with triple X syndrome have unaffected sexual development and have children.
Incidence: The overall birth incidence is 1 in 1,000 females, with a maternal age effect.
Chromosome result: 47,XXX .
Recurrence risk: The risk of recurrence does not appear to be increased above the general population risk.