Montevideo units

From Wikipedia, the free encyclopedia
Jump to: navigation, search

Montevideo units are a method of measuring uterine performance during labor. They were created in 1949 by two physicians, Roberto Caldeyro-Barcia and Hermogenes Alvarez, from Montevideo, Uruguay.

Units are calculated by internally (not externally) measuring peak uterine pressure amplitude (in mmHg), subtracting the resting tone of the contraction, and adding up the numbers in a 10-minute period.[1] Uterine pressure is generally measured through an intrauterine pressure catheter.

Montevideo units can be more simply calculated by summing the individual contraction intensities in a ten-minute period, a process which should arrive at a result identical to the original method of calculation.[2]

Generally, above 200 MVUs is considered necessary for adequate labor during the active phase.


If, for instance:

  • Peak uterine pressure amplitudes were 50 mmHg
  • during the 10 minute period of measurement 3 contractions occurred
  • subtract the resting tone from the peak intensity of the contraction
  • add the 3 contractions together to get the MVUs
  • Montevideo units are calculated by obtaining the peak uterine pressure amplitude and subtracting the resting tone. Then adding up those numbers generated by each contraction within a 10-minute window.
  • For example, five contractions occurred, producing pressure changes of 55, 50, 45, 65, and 50 mm Hg, respectively. The resting tone of the contractions is 10.

55-10 = 45 50-10 = 40 45-10 = 35 65-10 = 55 50-10 = 40

45+40+35+55+40 = 215 MVUs


  1. ^ "MATERNITY GUIDE - Labor & Delivery". Retrieved 2010-03-28. 
  2. ^ Ball, RH; Espinoza, MI; Parer, JT (1994). "Regional blood flow in asphyxiated fetuses with seizures". Am J Obstet Gynecol. 170 (1): 156–261. 

External links[edit]