title: Amniotic fluid volumetry by three-dimensional ultrasonography during the first trimester of pregnancy.
abstract: In a longitudinal prospective study, we quantitated the amniotic fluid volume (AFV) of 25 normal fetuses by endovaginal 3-D ultrasonography (3D-US) from the 8th to the 11th week of pregnancy. AFV by 3D-US was obtained by subtracting the volumetric measurement of the embryo (EV) from the amniotic sac volume (ASV). EV and ASV were obtained by virtual organ computer-aided analysis (VOCAL), using 6 degrees of rotation. AFV increased from 5.75 to 42.96 cm(3) from the 8th to the 11th week (ANOVA, p < 0.05), with a correlation between gestational age and AFV (p < 0.001, r(2) = 98.1%). We conclude that there was an increase in AFV assessed by 3D-US. The AFV values for normal fetuses can be used for comparison with those detected in pregnancies with risk of fetal loss.
authors.affiliation: Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil. patispara@yahoo.com.br
authors.forename: Patricia Spara
authors.initials: PS
authors.lastname: Gadelha
authors.forename: Antonio Gadelha
authors.initials: AG
authors.lastname: Da Costa
authors.forename: Francisco Mauad
authors.initials: FM
authors.lastname: Filho
authors.forename: Patricía
authors.initials: P
authors.lastname: El Beitune
mesh_terms: D000653:Amniotic Fluid / Q000000981:diagnostic imaging*; D005260:Female; D047109:Fetal Development; D005865:Gestational Age; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011446:Prospective Studies; D012016:Reference Values; D016216:Ultrasonography, Prenatal / Q000379:methods*