How Do You Calculate Montevideo Units

Montevideo Units (MVU) Calculator

Enter the peak intensity (in mmHg) for each contraction occurring within a 10-minute window.

Typical baseline is 5-15 mmHg

Result: 0 MVUs

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Understanding Montevideo Units (MVU)

Montevideo Units (MVU) are a clinical measure used in obstetrics to quantify the strength of uterine contractions during labor. This measurement is only possible when using an Internal Pressure Catheter (IUPC), which provides direct pressure readings from inside the uterus.

How to Calculate Montevideo Units

The calculation is based on a 10-minute monitoring window. To calculate MVUs manually:

1. Identify all contractions within a 10-minute period.
2. For each contraction, subtract the baseline uterine tone from the peak pressure (measured in mmHg). This gives you the amplitude.
3. Sum the amplitudes of all contractions in that 10-minute window.

Formula: MVUs = Σ (Peak Pressure - Baseline Tone) over 10 minutes

Clinical Significance

In clinical practice, MVUs help healthcare providers determine if labor is progressing adequately. While every patient is different, the following guidelines are generally used:

• Adequate Labor: Usually defined as achieving 200 to 250 MVUs in a 10-minute period.
• Inadequate Labor: If MVUs are consistently below 200 and the cervix is not dilating, it may indicate "hypotonic uterine dysfunction," which might require intervention such as oxytocin (Pitocin) augmentation.

Calculation Example

Imagine a 10-minute window with a baseline tone of 10 mmHg and 3 contractions:

• Contraction 1: Peak of 60 mmHg (60 – 10 = 50 amplitude)
• Contraction 2: Peak of 70 mmHg (70 – 10 = 60 amplitude)
• Contraction 3: Peak of 65 mmHg (65 – 10 = 55 amplitude)
• Total MVUs: 50 + 60 + 55 = 165 MVUs

In this example, the contractions might be considered inadequate for active labor progression, as the total is below the 200 MVU threshold.