title: Sirenomelia sequence: first-trimester diagnosis with both two- and three-dimensional sonography.
abstract: OBJECTIVE
  To describe the sonographic findings of sirenomelia during the first trimester on both two-dimensional sonography with color Doppler imaging and three-dimensional sonography.
  
  
  METHODS
  Two cases of sirenomelia in primiparous patients with histories of infertility are described. The diagnosis was made on the basis of two-dimensional sonography, and three-dimensional sonography was used to further characterize the findings.
  
  
  RESULTS
  Both fetuses had size-date discrepancies, increased nuchal translucency, large intra-abdominal vessels, and 2-vessel umbilical cords. Both pregnancies were terminated by dilation and curettage after the patients viewed the three-dimensional pictures of the fetuses.
  
  
  CONCLUSIONS
  During the first trimester of pregnancy, rare and lethal anomalies can be diagnosed with a high degree of confidence if a thorough, age-dependent anatomic survey of the fetus is performed.
authors.affiliation: Department of Obstetrics and Gynecology, New York University School of Medicine, New York, USA.
authors.forename: Ana
authors.initials: A
authors.lastname: Monteagudo
authors.forename: Patricia
authors.initials: P
authors.lastname: Mayberry
authors.forename: Andrei
authors.initials: A
authors.lastname: Rebarber
authors.forename: Michael
authors.initials: M
authors.lastname: Paidas
authors.forename: Ilan E
authors.initials: IE
authors.lastname: Timor-Tritsch
mesh_terms: D000025:Abortion, Eugenic; D000328:Adult; D004480:Ectromelia / Q000000981:diagnostic imaging*; D005314:Embryonic and Fetal Development; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D018615:Ultrasonography, Doppler, Color; D016216:Ultrasonography, Prenatal