<prompt> Fetal nuchal skin thickness is useful in detecting: March 2012Fetal infectionDown syndromeAnencephalyHydrops fetalis  <response>: Ans: B i.e. Down syndrome Increased fetal nuchal skin thickness in first trimester of more than 3 mm by TVS is a strong marker for chromosomal anomalies trisomy 21, 18, 13, triploidy and Turners syndrome. 