How long does active labour usually last for? When do you know that you are in active labour?

Active Labor is under phase 2 after early labor and before entering into phase 3 transitional labor. The active phase of labor usually lasts from two to three and a half hours as your cervix dilates to 7 centimeters. You'll usually be in the hospital or birthing center by this phase. Your contractions will grow more concentrated and increasingly more intense (in other words, painful). As they become stronger and longer (typically lasting 40 to 60 seconds, with a distinct peak halfway through) and more frequent (coming every three to four minutes, though the pattern may not be regular). http://www.whattoexpect.com/pregnancy/labor-and-delivery/childbirth-stages/three-phases-of-labor.aspx

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