Increased cerebrovascular morbidity was reported in adults born small for gestational age (SGA) who were treated with growth hormone (GH) during childhood compared to the general population. Yet, previous studies lacked an appropriate control group which is a major limitation. We prospectively studied cerebral white matter hyperintensities (WMHs) in adults born SGA at 12 years after cessation of childhood GH-treatment (SGA-GH), compared to appropriate controls. In this prospective cohort study, performed between May 2016 and December 2020, total WMHs, periventricular WMHs (PVWMHs) and deep WMHs (DWMHs) were the primary outcomes of the study, they were qualitatively assessed using 3Tesla (T) Magnetic Resonance Imaging (MRI) and scored using the Fazekas scale in SGA-GH adults and in 3 untreated control groups: adults born SGA with persistent short stature (SGA-S), adults born SGA with spontaneous catch-up growth to a normal height (SGA-CU) and adults born appropriate for gestational age with a normal height (AGA). Regression analyses were performed in the total cohort to evaluate the associations of GH-treatment and birth characteristics with WMHs. 297 adults were investigated (91 SGA-GH, 206 controls). Prevalence of total WMHs was 53.8% (95% CI 43.1-64.3) in SGA-GH, 40.5% (95% CI 25.6-56.7) in SGA-S, 73.9% (95% CI 61.9-83.7) in SGA-CU and 41.1% (95% CI 31.1-51.6) in AGA adults. No statistically significant differences in total WMHs, PVWMHs and DWMHs were found between SGA-GH compared to SGA-S and AGA adults. Highest prevalence of all type of WMHs was found in SGA-CU adults compared to all groups. Higher prevalence of total WMHs was associated with lower birth weight standard deviation score (SDS), but not with GH-treatment. Our findings suggest that GH-treatment in children born SGA has no negative impact on the prevalence of all type of WMHs at 12 years after GH cessation compared to appropriate controls. SGA-CU adults had the highest prevalence of all type of WMHs around age 30 years. Novo Nordisk.