Montevideo Unit Calculation and Clinical Interpretation

Measurement and Calculation

Montevideo Units are calculated as the sum of the amplitude above baseline of all uterine contractions occurring within a 10-minute window, measured by an intrauterine pressure catheter (IUPC), according to the American College of Obstetricians and Gynecologists 1, 2
An intrauterine pressure catheter (IUPC) or internal strain gauge must be used to obtain accurate pressure measurements, as recommended by the American College of Obstetricians and Gynecologists 1, 2
The catheter measures intrauterine pressure in millimeters of mercury (mm Hg), providing quantitative data needed for Montevideo Unit calculation, as stated by the American College of Obstetricians and Gynecologists 1, 2

Normal adequate uterine activity is generally considered ≥200 Montevideo Units, according to the American College of Obstetricians and Gynecologists 1, 2
Montevideo Units have significant limitations in clinical practice, including limited value in determining if a patient is in active phase of labor, as noted by the American College of Obstetricians and Gynecologists 1, 2
Cervical dilatation pattern remains the most reliable indicator for prospectively identifying the onset of active phase and assessing labor progression, as stated by the American College of Obstetricians and Gynecologists 1, 2