Purpose: To assess the outcome of fetuses with isolated mild ventriculomegaly (IMVM).
Materials and methods: The clinical course of 44 fetuses with IMVM was investigated. Cognitive and motor development was classified as normal or delayed.
Results: Clinical data were available for 37 subjects. Three (8%) neonates died. Of the 34 living children, follow-up was limited (< 9 months) in six and the clinical course beyond the 1st year of life was established in 28. Twenty-two (79%) of the 28 children are developing normally, whereas six (21%) are developmentally delayed. More than 90% of fetuses with ventricular atrial diameter of 10-11 mm are normal. Seventy-five percent of fetuses with IMVM were male. With exclusion of the six children with limited follow-up, 78% of boys older than 1 year are developmentally normal compared with only 50% of girls.
Conclusion: The majority of living children with prenatally detected IMVM are developmentally normal, especially those with borderline ventriculomegaly. Gender differences in prevalence and outcome deserve further investigation.