The 11-14-week scan helps to identify a high proportion of fetuses with trisomy 21 and other chromosomal abnormalities, major defects of the heart and great arteries, and a wide range of skeletal dysplasias and genetic syndromes. Other benefits include confirmation that the fetus is alive, accurate dating of the pregnancy, early diagnosis of major fetal defects, and the detection of multiple pregnancies and identification of chorionicity. The 11-14-Week Scan is a complete, authoritative clinician's textbook on using ultrasound as the main diagnostic tool in the prenatal detection of congenital abnormalities. It provides the basis of learning for the theoretical component of the Certificate of Competence in the 11-14-week scan awarded by The Fetal Medicine Foundation. The book covers early screening for chromosomal abnormalities, implications of increased nuchal translucency in chromosomally normal fetuses, ultrasound diagnosis of fetal ab normalities, determination of chorionicity and implications and management of multiple pregnancies, and multifetal pregnancy reduction.