Causes of prolonged first stage of labor are all except: March 2009

Ans. C: Rigid Perineum The first stage stas with uterine contractions leading to complete cervical dilation and is divided into latent and active phases. In the latent phase, irregular uterine contractions occur with slow and gradual cervical effacement and dilation. The active phase is demonstrated by an increased rate of cervical dilation and fetal descent. The active phase usually stas at 3-4 cm cervical dilation and is subdivided into the acceleration, maximum slope, and deceleration phases. The second stage of labor is defined as complete dilation of the cervix to the delivery of the infant. The third stage of labor involves delivery of the placenta. Prolonged first stage of labour Latent phase: Diagnosis of abnormal labor during the latent phase is uncommon and likely an incorrect diagnosis. Active phase: Around the time uterine contractions cause the cervix to become 3-4 cm dilated, the patient usually enters the active phase of the first stage of labor. There may be abnormalities of cervical dilation (protracted dilation and arrest of dilation) or descent abnormalities (protracted descent and arrest of descent). In general, abnormal labor is the result of problems with one of the 3 P' s. Passenger (infant size, fetal presentation) Pelvis or passage (size, shape, and adequacy of the pelvis) Power (uterine contractility)