Induction and The Friedman’s Curve Downfall
Have you ever heard someone say, “My pelvis was too small” or “I was diagnosed with Failure to Progress?”
What is Friedman’s Curve and Why Does It Matter?
In 1955, Dr. Emanuel Friedman of Columbia University published a study that described the average amount of time it takes to dilate by a centimeter based on his observation of 500 patients at a single hospital in New York City (Friedman, 1955). The graph that he created from these people giving birth for the first time (and later in a similar study with people who had given birth before (Friedman, 1956) went on to become known around the world as “Friedman’s Curve.”
What do we know about the 500 participants in the study? There were no women of color included in the study due to segregation. Their ages ranged from 13 to 42 years old, and most (70%) were between the age of 2030. More than half had forceps used on them during delivery (55%), and only nine (1.8%) gave birth by Cesarean. There were 14 breech births (2.8%), four twin births (0.9%), and four stillbirths or newborn deaths. The babies ranged in weight from 4 lbs. 9 oz. to 10 lbs. 6 oz., with most babies falling into a normal weight range (5 lbs. 8 oz. to 8 lbs. 13 oz.). Pitocin was used to induce or augment labor in only 69 people (13.8%).
Back then, “Twilight Sleep” was common practice for white birthing patients (it was usually not offered to Black patients), and so 117 of the participants (23%) were lightly sedated, 210 (42%) were moderately sedated, and 154 (31%) were deeply (sometimes “excessively”) sedated with Demerol and Scopolamine. This means that 481 (96%) of the 500 people giving birth were sedated with drugs (Friedman, 1955).
So, why does this matter? Friedman’s Curve was the gold standard in American obstetrics care until the 2010s. Think about that, friend. 55 years of this skewed data ruling our model of maternal care. Crazy right? Thankfully it’s been a slow change thanks to ACOG and new studies paving the way!
The Evolving Guidelines
In one important study published in 2010, Zhang’s Study, researchers looked at the labor records of more than 62,000 people from 19 hospitals across the U.S. Participants were included if they gave birth vaginally at term to a single baby who was positioned head-down if the babies were born healthy, and if the labors started spontaneously (were not medically induced). Most of the birthing people had interventions during their labors—overall, about half of them had their labors “augmented” or sped up with oxytocin (Pitocin), and 80% had epidurals (Zhang et al. 2010).
The researchers found that on average, people did not rapidly dilate starting at four cm as Dr. Friedman saw back in 1955. Instead, active labor was reached at around six cm. This was true for both people giving birth for the first time and those who had given birth before, although those who had given birth before tended to dilate faster once they reached active labor (six cm). The average time it took to dilate during active labor was about half an hour for each centimeter (and faster for those who had given birth before). The vast majority of people (95%) took less than two hours to dilate one cm during active labor.
Interestingly, researchers found that before six cm, many people (both people giving birth for the first time and those who had given birth before) went long periods without any dilation—and this was within the range of normal in the sample. For example, those laboring took an average of 1.8 hours to get from three cm to four cm, but the top 5th percentile of the sample (still in the range of normal) took as long as 8 hours. On average, people took 1.3 hours to get from four cm to five cm, but the top 5% took seven hours. Remember: all these people went on to give birth vaginally to healthy babies.
When it came to pushing or the “second stage” of labor, first-time parents pushed for an average of 1.1 hours with an epidural and 0.6 hours without an epidural. At the very extreme end of normal, some first-timers (the 5% that pushed the longest) pushed for 3.6 hours with an epidural and 2.8 hours without an epidural. Those that had given birth before had much shorter pushing phases—on average, they spent less than 30 minutes pushing with an epidural, and about 15 minutes without an epidural.
Failure To Progress, Induction, and How To Influence Labor
So much of labor, like most things with our body, can trigger a domino effect. Fear of labor/pain can lead to slow progression, which then can turn into failure to progress. Induction can lead to slower early labor, higher exhaustion levels, and increased chances of a failure to progress diagnosis. So on and so forth, this could go on forever with so many scenarios! None of this is black & white or guaranteed to happen. Let’s look at some ways you can encourage labor progression.
Upright positions during labor - let gravity do most of the work!
Doula support during labor - There’s scientific evidence that speaks to the amazing impact doula support can have on labor.
Fetal Positioning - where is that sweet baby at? Is the head fully engaged? Does your body need time to ‘labor down’?
Pelvic Balance & Pelvic Floor - Use movement to balance your pelvis…if you do a stretch or a lunge on the right, do the same to the left.
Labor Augmentation - Pitocin, membrane strip, breaking your waters, etc.
Oxytocin & Environment - Remember how I said fear can be that trigger for a domino effect? Keep the environment calm, dim the lights, and keep distractions to a minimum. Combine this with keeping the oxytocin flowing…girl, it can be magic! Cuddle your partner, share kisses, take a shower together, and look at sonogram photos or pictures of your other children. Anything to keep that love hormone flowing!
Let’s chat if you’d like to learn more! I’d love to support you during your labor and birth!
