Intrauterine treatment of fetal cerebral ventriculomegaly has been largely abandoned, as the results have been disappointing compared with those of standard neonatal treatment. However, we suggest that the natural history of ventriculomegaly diagnosed in utero has not been studied adequately and that fetal surgery may have a role in selected patients. We have analyzed the outcome in 43 cases of fetal ventriculomegaly followed up without active treatment in utero. Our data suggest that the prognosis is poor for fetuses with ventriculomegaly and coexistent malformations, good for those with isolated, nonprogressive ventriculomegaly, and variable for those with progressive, isolated ventriculomegaly.