title: Sonographic visualization of the ovaries throughout pregnancy.
abstract: OBJECTIVE
  To determine the frequency with which one or both normal ovaries can be visualized during a routine obstetric ultrasound examination.
  
  
  METHODS
  The population consisted of 5617 pregnant women at 5.0-39.9 weeks' gestation, studied cross-sectionally. The sonographic visualization rate for one or both normal ovaries, as well as their position above or below the level of the umbilicus, was recorded for one examination in each patient.
  
  
  RESULTS
  The study population was divided into three groups according to gestational age: first trimester, 5.0-12.9 weeks; second trimester, 13.0-26.9 weeks; and third trimester, 27.0-39.9 weeks. There were 829, 3195, and 1593 women in the first, second, and third trimesters, respectively. Most women were examined transvaginally in the first trimester; transabdominal sonography was used in the second and third trimesters. The ability to visualize one or both ovaries declined significantly (P < .05) from the first trimester to the second, as well as from the second trimester to the third (P < .001). The percentage of ovaries that were visualized above the umbilicus increased from 2.4% in the first trimester to 10.1% in the second trimester (P < .001), and to 21.7% in the third trimester (P < .001).
  
  
  CONCLUSIONS
  As gestational age advances, there is a significant reduction in the ultrasound visualization rate of normal ovaries. This investigation provides normative data for ovarian visualization throughout pregnancy that may be helpful in establishing ultrasound laboratory standards.
authors.affiliation: Department of Obstetrics, Gynecology, and Reproductive Sciences, Magee-Womens Hospital, University of Pittsburgh School of Medicine, Pennsylvania, USA.
authors.forename: L M
authors.initials: LM
authors.lastname: Hill
authors.forename: J G
authors.initials: JG
authors.lastname: Martin
authors.forename: K
authors.initials: K
authors.lastname: Deutsch
authors.forename: C
authors.initials: C
authors.lastname: Merolillo
authors.forename: J
authors.initials: J
authors.lastname: Leary
mesh_terms: D005260:Female; D006801:Humans; D010053:Ovary / Q000000981:diagnostic imaging*; D011247:Pregnancy / Q000502:physiology*; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D016216:Ultrasonography, Prenatal