Latent phase of labor
- Andrew J Satin, MD, FACOG
Andrew J Satin, MD, FACOG
- The Dorothy Edwards Professor and Director of Gynecology and Obstetrics
- Johns Hopkins University School of Medicine
Normal labor refers to the presence of regular uterine contractions that cause progressive dilation and effacement of the cervix and fetal descent. It is viewed in terms of its phases: latent, active, and decelerative; and its stages: first, second, and third.
The latent phase of labor will be reviewed here. Other aspects of labor and labor abnormalities are discussed separately:
Latent phase — The initial phase of labor is termed the latent phase. It begins at the point at which the woman perceives regular uterine contractions. These contractions gradually soften, efface, and begin to dilate the cervix. This simple definition belies a complex process not completely understood by modern science. Women have irregular contractile activity beginning in the midtrimester, and gradual changes in the consistency, position, dilation, and effacement of the cervix occur over the remaining months of the pregnancy [1,2]. This makes accurate assessment of the onset of latent phase difficult since determining exactly when a patient has entered latent phase is primarily based upon the woman's history and the judgment of the attending provider.
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