How to Time Contractions: Duration vs. Frequency

When someone asks how far apart your contractions are, there are two measurements to keep separate: how long each contraction lasts and how often a new one begins.

Duration: how long one contraction lasts

Start the timer when you notice the contraction beginning. Stop when that contraction has ended. The time between those two points is its duration.

For example, a contraction that begins at 8:00:00 and ends at 8:00:45 lasts 45 seconds.

Frequency: how often contractions begin

Measure from the beginning of one contraction to the beginning of the next. Include the contraction itself and the pause afterward.

If one contraction starts at 8:00 and the next starts at 8:06, they are 6 minutes apart. That does not mean you had 6 minutes of rest between them.

A Simple Example

Contraction starts Contraction ends Duration Time until the next contraction starts

8:00:00 8:00:45 45 seconds 6 minutes

8:06:00 8:06:50 50 seconds 5 minutes

8:11:00 8:00:55 55 seconds Not yet known

This is an example for practicing the measurements, not a rule for when to leave for the hospital.

What to record

Use a contraction app or a simple note with three columns: start time, end time, and duration. Add the time from each start to the next start as you go. You can also note how the contractions feel and whether the pattern is changing.

Timing is only part of the picture

Follow the calling and arrival instructions your maternity care team gives you. Ask during pregnancy which instructions apply to your situation.

If you are worried, call rather than waiting to finish a timing log. Contact your maternity team promptly if your waters break, you have vaginal bleeding, your baby is moving less than usual, or you think labor may be starting before 37 weeks. Do not wait for contractions to meet a particular pattern before reporting those concerns.

General education only. Your maternity care team can help you interpret your symptoms and decide what to do next.

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