IQ fell in a male patient whose puberty was blocked due to gender distress.

A case study¹ of a male patient whose puberty was blocked at age 11 showed a decline in several measurements of intelligence over the following three years, including decline of 10 points in global IQ and 15 points in verbal comprehension. 

Verbal comprehension showed a continuous decline. Other measurements showed some improvement after an initial decline, but never recovered to baseline levels. Processing speed index scores initially improved, but then fell below baseline.

1. Schneider MA, Spritzer PM, Soll BMB, Fontanari AMV, Carneiro M, Tovar-Moll F, Costa AB, da Silva DC, Schwarz K, Anes M, Tramontina S, Lobato MIR. Brain Maturation, Cognition and Voice Pattern in a Gender Dysphoria Case under Pubertal Suppression. Frontiers in Human Neuroscience. 2017 Nov 14;11:528. doi: 10.3389/fnhum.2017.00528. PMID: 29184488; PMCID: PMC5694455. ↩︎