Ancillary benefits of prenatal maternal serum screening achieved in the California program

Abstract

Objective: To evaluate the extent of fetal structural abnormalities, other than neural tube and abdominal wall defects (AWDs), identified by California's Prenatal Screening Program. Methods: The Quad Marker Prenatal Screening records of 516,172 women were examined for screening interpretation and the diagnosis of structural abnormalities detected via follow-up. Women who were screenpositive for trisomy 21, trisomy 18, neural tube defects (NTDs) or Smith-Lemli-Opitz syndrome (SLOS) received follow-up services at state-approved Prenatal Diagnosis Centers (PDCs). Detailed reports of services and diagnostic information were linked in a database to the original screening results. Results: A total of 26 323 women received follow-up ultrasound services at the PDCs in the study time period. Of these women, 1085 (4.1%) were identified as having fetuses with significant structural abnormalities, other than NTDs (n = 207) or AWDs (n = 254). In addition to the structural abnormalities, 225 cases of fetal demise, 4 molar pregnancies, 15 cases of twin-to-twin transfusion, and 92 cases with placental abnormalities were identified. Conclusion: While Prenatal Screening Programs do not explicitly screen for structural abnormalities other than NTDs and AWDs, clearly many other structural abnormalities may be associated with a screen-positive status. Thus, the detection of these additional structural defects can be considered an ancillary program benefit. Copyright © 2010 John Wiley & Sons, Ltd.