Evidence based considerations regarding the new ACOG labor guidelines

Recent guidelines issued jointly by the American College of Obstetrics and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine for assessing labor differ substantially from those described initially by Friedman, who led obstetric practice for decades. The new recommendations are based on results achieved by the analysis of patterns of cervical dilation and fetal descent. They argue that labor models originally described by Friedman are no longer applicable to modern obstetrical practice. The main changes proposed to the Friedman curve are considered to be that the beginning of the active phase is from 6 cm opposed to 4 cm. The diagnosis of dystocia is established for a progression of dilatation under 0.5 cm/h opposed to 1.5-1.2 cm. Accepted duration of the expulsion is amended: over 3 hours for nulliparous and over 2 hours for mulliparous. The new ACOG guidelines revised birth periods favoring a more permissive in terms of time factor.