@inbook{1138213470, author={Edward R. Yeomans and Barbara L. Hoffman and Larry C. Gilstrap III and F. Gary Cunningham}, title={Invasive Prenatal Diagnostic Procedures}, booktitle={Cunningham and Gilstrap's Operative Obstetrics, 3e}, publisher={McGraw-Hill Education}, address={New York, NY}, year={2017}, url={obgyn.mhmedical.com/content.aspx?aid=1138213470} }