title: Amniotic sac, fetal heart area, fetal curvature, and other morphometrics using first trimester vaginal ultrasonography and color Doppler imaging.
abstract: Ultrasonographic morphometric measurements were obtained with transvaginal ultrasonography from 121 patients with first trimester singleton pregnancies. Amniotic and gestational sac diameters, fetal heart area, and fetal length increased in a linear rate relative to crown-rump length, whereas the amniotic and gestational sac volumes increased at an exponential rate. The yolk sac exhibited a biphasic growth pattern with a peak at a crown-rump length of 3.5 cm. The ratio of crown-rump length to anteroposterior dimension increased over the first trimester, suggesting less curvature in older fetuses. In conclusion, vaginal ultrasonography permits accurate measurement of many new morphometric parameters.
authors.affiliation: Department of Obstetrics and Gynecology, Columbia Presbyterian Medical Center, New York, New York.
authors.forename: E Z
authors.initials: EZ
authors.lastname: Zimmer
authors.forename: C R
authors.initials: CR
authors.lastname: Chao
authors.forename: R
authors.initials: R
authors.lastname: Santos
mesh_terms: D000650:Amnion / Q000000981:diagnostic imaging*; D018568:Crown-Rump Length; D004452:Echocardiography; D005314:Embryonic and Fetal Development; D005260:Female; D005318:Fetal Heart / Q000000981:diagnostic imaging*; D005333:Fetus / Q000033:anatomy & histology; D006340:Heart Rate, Fetal; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012016:Reference Values; D018615:Ultrasonography, Doppler, Color; D016216:Ultrasonography, Prenatal / Q000379:methods*