Objective      To evaluate the importance of the prenatal diagnosis to fetus with mild ventriculomegaly（MVM）in pregnancy outcome and prognosis.       Methods      The ultrosonographic results of 10 485 pregnant women with a meanage of 29±6 and a pregnancy period of 22 to 34 weeks who were admitted to our hospital from Jan 2009 to Oct 2010 were collected in this study. The clinical data of fetuses with mild ventriculomegaly

including the results of ultrasonography

magnetic resonance imaging (MRI) and chromosome examination were retrospectively analyzed. Follow-up was done upon live fetus after delivery.       Results      Ultrasonography indicated there were 53 fetuses with mild ventriculomegaly

with an incidence rate of 0.5% (53/10 485). Forty of them were detected in the pregnancy period of 22 to 28 weeks

and the left were identified in the 28 weeks later

even in 34 weeks. The incidence of MVM complicated with other abnormities was 37.7%

and that complicated with chromosome disorder was 9.4%. Thirty-nine fetuses with MVM were examined by MRI

and thirty-four results of MRI were consistent with ultrasound results

with a consistence rate of 87.2%. There were 33 infants born live (62.3%)

and 25 of them were in normal growth and development

accounting for 75.8%.       Conclusion      Ultrasonography and MRI play an important role in the detection of MVM. Chromosome analysis should be carried out for elder pregnant women when their fetuses are diagnosed as MVM and other complicating abnormities.