The outcome of non-progressive, isolated fetal ventriculomegaly is uncertain. The normal width of the atrium of the lateral ventricle is less than or equal to 9 mm.1 Severe ventriculomegaly (or hydrocephalus) is defined as widths greater than 15 mm. Mild values of 10–15 mm confer an increased risk for aneuploidy, malformations and impaired postnatal neurological outcome, although the frequency of the association is variable.2^–4 However, the outcome of fetal non-progressive isolated forms of lateral ventriculomegaly with atrial widths between 10 and 12 mm has been little studied. It is, therefore, difficult to provide appropriate counselling in such cases. A recent series5 suggested that outcomes in patients …