Journal of Ultrasound in Medicine, Vol 17, Issue 10 661-665, Copyright © 1998 by American Institute of Ultrasound in Medicine
Myometrial thickness in pregnancy: longitudinal sonographic study
S. Degani, Z. Leibovitz, I. Shapiro, R. Gonen and G. Ohel
Department of Obstetrics and Gynecology, Bnai-Zion Medical Center, and The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa.
The purpose of this study was to evaluate in vivo the changes in myometrial
thickness throughout pregnancy. Myometrial thickness was measured in 25
singleton uncomplicated pregnancies. Ultrasonographic sagittal and
transverse sections were used to measure uterine wall thickness from the
low anterior wall (lower segment) and the anterior, posterior, right, and
left walls of the upper segment and from the fundus. In each case four
measurements were made in the second and third trimesters. Myometrial
thickness of the upper uterine segment remains fairly constant in the first
and second trimesters of pregnancy, whereas a significant linear trend was
found between a decreasing thickness of the lower uterine segment and
advancing gestational age. Myometrial thickness is significantly increased
behind the placental insertion site as compared to other portions of the
uterine wall. These data may serve as baseline reference values for further
studies in the antepartum fetal surveillance of high-risk pregnancies.
