This is also a time when the discomfort of the contractions makes a big leap in discomfort. This is when reflexes kick in to stimulate more contractions to cause more dilation-a vicious cycle of sorts. The latent phase of labor will dilate the cervix form 0-3 cm, and it will begin a transition to an active phase at about 4 cm. However, a woman that dilates from 3 cm to 4 cm in association with rhythmic contractions is in active labor. To illustrate, a woman is not in active labor if she is multiparous and has a cervical dilation of 3-4 cm which has been the same for a month.

This is why the active phase is defined as the active dilation of the cervix. Multiparas often are dilated to some extent at term, before labor, because of weakness in the cervix from previous delivery. Therefore, primigravidas often are undilated at term. Alternatively, many multiparas (women who have experienced childbirth before) have a 'used' cervix-one that has been stretched and then reformed, at least once-perhaps many times. Primigravidas (women experiencing their first pregnancy) have a cervix which has never been dilated. As the cervix yields-as its fiborelastic circumference weakens-it begins to thin out and open, its circular structure said to dilate. ACTIVE PHASE: The active phase of labor actively dilates the cervix by a process of progressively more frequent and strengthening contractions.Īs opposed to latent phase contractions, these are organized into a net vector force downward, pushing the infant's presenting part (usually the head), as a dilating wedge against the cervix.Latent phase is a phase of actual labor, doesn't come and go, but progresses on to active labor.But this is not the best way to think of it. Latent phase of labor is often referred to as ' false' labor because it does not actively dilate the cervix and it may spontaneously resolve without progressing into active labor. The time between contractions is called the ' refractory' period, and the refractory periods during the latent phase of labor can be from under a minute to as long as a half-hour. During the latent phase, although the contractions are constant, they are not really rhythmic. LATENT PHASE: Stage 1 begins when contractions become constant, although the time between them can vary during a beginning, or, ' latent' phase.It does not include ' Braxton-Hicks' contractions, which are disorganized contractions that can occur anytime after 20 weeks gestation (halfway through the pregnancy). This is from the time of active dilation of the cervix until complete dilation (usually 10 cm.). Stage 3 is from delivery until placental delivery.Stage 2 is from complete dilation to delivery.Stage 1 is a progression from latent phase to active phase, until complete dilation is accomplished.Labor and delivery are delineated into Stages 1, 2, and 3.

Transition phase of labor