Maternal Serum Analyte Screening for Fetal AneuploidyCHASEN, STEPHEN T. MD*,†Clinical Obstetrics & Gynecology: March 2014 - Volume 57 - Issue 1 - p 182–188 doi: 10.1097/GRF.0000000000000017 Noninvasive Screening for Fetal Aneuploidies: Eliminating Unwanted Surprises Abstract Author Information In the first and second trimesters, chemicals produced by the fetoplacental unit are measured to assess risks of fetal abnormalities. Consistent associations between levels of these proteins in such pregnancies enable these biomarkers to be used to calculate risk for Down syndrome and other chromosomal abnormalities in individual pregnancies. Special consideration may be required when assessing risk in multiple pregnancies and pregnancies achieved with infertility therapy. *NewYork-Presbyterian Hospital; †Weill Cornell Medical College, New York, New York The author declares that there is nothing to disclose. Correspondence: Stephen T. Chasen, MD, Weill Cornell Medical College, New York, NY. E-mail: email@example.com © 2014 by Lippincott Williams & Wilkins.