Aim: The aim of this article was to clarify the impact and consequences of very preterm birth (born less than 32wks of gestation) and/or very low birthweight ([VLBW], weighing less than 1500g) on brain volume development throughout childhood and adolescence. Method: The computerized databases PubMed, Web of Knowledge, and EMBASE were searched for studies that reported volumetric outcomes during childhood or adolescence using magnetic resonance imaging and included a term-born comparison group. Fifteen studies were identified, encompassing 818 very preterm/VLBW children and 450 term-born peers. Average reductions in the total brain volume, white matter volume, grey matter volume, and in the size of the cerebellum, hippocampus, and corpus callosum were investigated using meta-analytic methods. Results: Very preterm/VLBW children were found to have a significantly smaller total brain volume than the comparison group (d = -0.58; 95% confidence interval [CI] -0.43 to -0.73; p less than 0.001), smaller white matter volume (d = -0.53; CI -0.40 to -0.67; p less than 0.001), smaller grey matter volume (d = -0.62; CI -0.48 to -0.76; p less than 0.001), smaller cerebellum (d = -0.74; CI -0.56 to -0.92; p less than 0.001), smaller hippocampus (d = -0.47; CI -0.26 to -0.69; p less than 0.001), and smaller corpus callosum (d = -0.71; CI -0.34 to -1.07; p less than 0.001). Reductions have been associated with decreased general cognitive functioning, and no relations with age at assessment were found. Interpretation: Very preterm/VLBW birth is associated with an overall reduction in brain volume, which becomes evident in equally sized reductions in white and grey matter volumes, as well as in volumes of diverse brain structures throughout childhood and adolescence.