Bartholomew's rule of fourths

Bar·thol·o·mew's rule of fourths

(bär-thŏl′ə-myōōz′)
n.
A rule for determining the duration of pregnancy by measuring the height of the fundus of the uterus above the pubic symphysis.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.