Aneuploidy and isolated mild ventriculomegaly - Attributable risk for isolated fetal marker

Background: Does the prenatal ascertainment of isolated mild ventriculomega ly increase the a priori risk for aneuploidy when isolated or not associate d with advanced maternal age? Does isolated mild ventriculomegaly increase the risk for pediatric developmental delay? Methods: The Wayne State Univer sity (WSU) Reproductive Genetics abnormal case data base and the Madigan Ar my Medical Center (MAMC) experience were reviewed to compare the rates of a neuploidy for cases with fetal ventriculomegaly, Cases were classified by m aternal age and associated sonographic markers of aneuploidy, Aneuploidy ra tes were compared between the isolated ventriculomegaly, ventriculomegaly w ith advanced maternal age (AMA), and ventriculomegaly associated with multi ple anomalies. Rates of aneuploidy were compared to identify association. R esults: A total of 118 cases with ventriculomegaly were identified for comp arison. Ninety-four cases were identified in the WSU cohort; 46 demonstrate d isolated ventriculomegaly alone, and aneuploidy was present in 3/25 (12%) with invasive fetal testing, 0/24 (0%) cases in the MAMC cohort demonstrate d aneuploidy. Isolated mild ventriculomegaly cases at MAMC were identified for further tests. Discussion: Although the two study populations vary in a ge a nd risk distributions, the attributable risk for isolated mild ventric ulomegaly poses a counseling conundrum due to the neurodevelopmental implic ation of this minor dysmorphism more so than its association with aneuploid y. Copyright (C) 2000 S. Karger AG, Basel.