Montevideo units for measurement of uterine activity include:
Ans. a (Ref. Danforth's Obstetrics and Gynecology, 9th/01.9)UTERINE ACTIVITY# The normal frequency of uterine contractions during labor is every 2 to 3 minutes; however, cervical change may result from contractions occurring less frequently. In most cases, five to seven uterine contractions within a 15-minute period reflect adequate uterine activity. Increased contraction frequency is termed uterine tachysystole and is defined by six or more uterine contractions within a 10-minute window for two consecutive windows.# The duration is assessed by calculating the length of the contraction, the fine vertical lines represent 10-second intervals, and heavy lines denote 1-minute intervals (run at 3 cm per minute). Normal uterine contractions last approximately 40 to 60 seconds.Prolonged contractions may result from "coupling" of contractions, uterine hyperstimulation, or acute complications such as placental abruption or uterine rupture.# The strength of the contractions can only be assessed with the direct Intrauterine Pressure Catheters (IUPC). The normal baseline uterine pressure between contractions is approximately 10 mm Hg.# Abnormally high baseline pressures in excess of 20 mm Hg may result from hyperstimulation or occasionally from overdistention of the uterus by excessive amnioinfusion, polyhydramnios, or fetal macrosomia. During contractions, normal uterine pressure ranges from 30 to 80 mm Hg, although pressures in excess of 80 mm Hg may be observed during the second stage of labor.The Montevideo unit = The Average intensity of the uterine contractions multiplied by the number of contractions over a 10-minute period (expressed as mm Hg/10 min).# Montevideo units in excess of 180 to 200 usually are considered to reflect adequate uterine activity to effect cervical change in labor.# A total of 200 Montevideo units indicates that there is adequate uterine contractility to effect labor progress.
Increased is uterine pressure (mm of Hg) x number of contractions every 10 minutes
Increase in uterine pressure (mm of water) x number of contractions every 10 minutes
Increased in uterine pressure (cm of water) x number of contractions every 10 minutes
Increase in uterine pressure (cm of H20) x number of contractions every 20 minutes
Miscellaneous (Gynae)