Reevaluation of Friedman's Labor Curve: a pilot study

To reevaluate the average length of each phase/stage of labor for multiparous and primiparous women in North America who received no regional anesthesia or oxytocin augmentation or induction, to describe a range of labor lengths associated with good childbirth outcomes, and to determine if there is a consensus among labor and delivery nurse managers responding to the survey regarding the need to revise Friedman's Labor Curve.

This pilot study used a descriptive and anonymous cross-sectional survey design. Surveys were mailed to 500 maternity care agencies in the United States, Canada, and Mexico with a return rate of 17.8% (n = 89). Each participating agency was asked to submit five patient cases to be included in the analysis.

The sample of patient cases (n = 419) was drawn from randomly selected maternity care agencies throughout North America representing all sizes of agencies and geographic locations. The cases submitted for analysis represented women 14 to 44 years of age with varying ethnicities who received no regional anesthesia or oxytocin augmentation or induction. Twenty-three percent of the women in the sample (n = 97) were primigravidas.

The average length of labor for primiparous and multiparous women today is similar to the average length of labor described by Friedman in 1954. However, a wider range of "normal" was found in cases included in the current study. Primiparous women remained in the first stage of labor for up to 26 hours and the second stage of labor up to 8 hours with no adverse effects to mother or infant. Multiparous women remained in the first stage of labor for up to 23 hours and the second stage of labor for up to 4.5 hours with good birth outcomes. In addition, 87.6% of nurse managers responding to the survey believed that Friedman's Labor Curve should be revised to meet the needs of current patient populations, technological advances, and nursing responsibilities.

This study suggests that the parameters to determine if a labor is progressing satisfactorily may need to be expanded. With the availability of technology to assess maternal and fetal well-being, labor should be allowed to progress past the rigid 2-hour time limit for the second stage of labor artificially imposed on women in some childbirth settings. More emphasis should be placed on the nursing assessment techniques used to reassure the family and health care practitioners that labor is progressing safely and the nursing interventions that may have an impact on the length of each stage of labor.