Second-trimester pregnancy associated plasma protein-A levels are reduced in Cornelia de Lange syndrome pregnancies

Maternal serum samples were collected from 19 pregnancies which resulted in the birth of a child with the classical Cornelia de Lange syndrome phenotype ascertained by careful clinical review. Using specific immunoassays, the serum levels of pregnancy associated plasma protein‐A, free‐beta human chorionic gonadotrophin and inhibin A were investigated. Pregnancy associated plasma protein‐A was detectable in all cases but the levels were significantly reduced in second‐trimester maternal serum from 18 affected pregnancies. Expressed as multiples of the median (MOM), the results ranged from 0.03 MOM to 0.71 MOM with an overall median value of 0.21 MOM (Mann–Whitney p