Emanuel A.
Friedman M.D., of Columbia University, introduced the labor curve, commonly
known as “Friedman’s Curve ” to depict the average amount of time it took for a
labor patient to dilate each cm. Published nearly 60 years ago, the curve is
still followed by a majority healthcare providers to define normal labor.
In 2012,
when the National Institute of Child Health and Human Development (NICHD), the
Society for Maternal and Fetal Medicine (SMFM), and ACOG held a workshop aimed
at “preventing the first Cesarean.” In the workshop, it was discussed that many
cesarean sections are simply performed because many women are wrongly
categorized as “ failure to progress” based on Friedman’s Curve.
In 2014,
ACOG and SMFM issued a consensus statement “Safe Prevention of the PrimaryCesarean Delivery ” to bring down the rising cesarean section rates. The
statement redefined normal and abnormal labor and stated that Friedman’s Curve
should no longer be used as the basis for modern labor management (ACOG 2014).
A critical
study published by Zhang et al. formed the basis of the new guidelines. The
study was based on data from the Consortium on Safe Labor and looked at labor
records of 62,000 women from 19 hospitals across the U.S. The researchers
concluded that “ failure to progress” should be diagnosed at 6 cm and not 4 cm
as stated earlier.
ACOG also
reaffirmed this statement in 2017 and again in 2018 ACOG Committee Opinion No.766: Approaches to Limit Intervention During Labor and Birth.
Here is an
interview with Emanuel A. Friedman about definitions of active and in active
labor. He opines that “Woman describes her own labor curve, it is irrelevant to
designate a particular point in labor as a demarcation between active and in
active labor.”
