In Rett syndrome, after what age do individuals typically experience regression?

In Rett syndrome, individuals usually experience regression of skills after approximately 18 months of age. This milestone is critical because, up until around that time, children may appear to be developing typically, demonstrating normal early motor and social skills. However, after 18 months, there is often a noticeable decline in these abilities, including loss of purposeful hand skills, reduced communication, and social engagement.

This regression is a hallmark of Rett syndrome and distinguishes it from other developmental disorders, where regression may not be as clearly defined or may occur at different stages. The age of 18 months marks a significant transition point in the development trajectory for those affected by the condition. Recognizing this timing is important for diagnosis and intervention, allowing caregivers and healthcare professionals to provide appropriate support during this challenging period.