Hypertension and pregnancy and preventing the first cesarean delivery
A peer-to-peer audiocast with John T. Repke, MD, and Errol R. Norwitz, MD, PhD
Preventing the first cesarean delivery. Will cesarean rates decline?
Dr. Repke: So, speaking of guidelines, the Society for Maternal Fetal Medicine (SMFM) just came out with a document trying to address this issue of the cesarean-section rate in the United States and are there things that we can be doing to lower the primary C-section rate.2 My feeling is probably disseminated from the recognition that vaginal birth after C-section never got to the levels of acceptance that anybody hoped back when Healthy People 2010 was first written. And, we could eliminate that issue or, at least significantly reduce that issue, if the first C-section never took place.
And, I guess I’d like some of your thoughts about some of the things in that document, some of the things we need to be reconsidering in terms of how we define labor and so on.
Dr. Norwitz: It is true, I think, that there’s been an epidemic of cesarean deliveries in the last decade in the US, but also throughout the world, I think, even in countries that have traditionally had very low cesarean delivery rates, the classic one being Ireland and the UK countries. Their rates are now increasing significantly.
And there are a number of different reasons as to why this may be. I think, certainly the obesity epidemic has contributed to this. You want to deliver patients who have an elevated BMI prior to the postterm period. But, it’s often difficult to monitor these patients, and the cesarean-delivery rate overall is much higher in that population. So, that might be one reason why cesarean-delivery rates overall are going up. But, certainly there are many others.
Dr. Repke: Yes, I think you’re absolutely right: the demographics of change. Childbearing is being delayed. We know that uterine contractility dynamics alter with advanced maternal age. We’ve got a higher incidence of multiple gestations with advanced maternal age. We have more patients that require induction because of supervening medical complications of pregnancy, whether that be Class A2 gestational diabetes, or whether that be pregnancy-induced hypertension.
Redefining the stages of labor
Dr. Repke: I think some of the intriguing data, to me, is a willingness to re-look at how we define the stages of labor. And what are acceptable norms? And, while I have some concerns about how that may be interpreted in the rank and file, I think it’s at least heightened the awareness of my faculty that we just can’t tolerate the C-section at 4 cm, or whether the latent phase of labor should be allowed to go to 6 cm. I don’t think we really have the data for that. But I’d be happy if I could just start to see a reduction in “failure to progress at 4 cm.”
And then the issue of second stage, I think, is also important. What do you think about the guidelines’ recommendation that there may not really be an upper limit of allowability for second-stage labors?
Dr. Norwitz: Well, certainly I think it’s important to think back to the historical context of where the labor curves developed. The original labor curves were actually developed in Zimbabwe (at that time it was Rhodesia) by an obstetrician working in the community called Philpott. And he was trying to determine when it was appropriate to send patients into the tertiary care center. So he designed the labor curve and said if patients failed to progress over a certain number of hours, those are patients that are likely to need an operative delivery, and he would then send them into the tertiary care center.
And, then Dr. Freidman picked up on that idea and developed the Freidman Curve in Boston. But that was an era, again, many years ago when the population demographics were very different, when not many patients received regional anesthesia. I think if you look at the current guidelines, there is a huge discrepancy between women who get epidural anesthesia and those that don’t in terms of the progress of labor, both the first stage and the second stage.
Is it anesthesia?
Dr. Repke: One of the things that, you know, I haven’t looked at this paper in a long time, but you remember at Brigham and Women’s Hospital, probably 20 years ago, we were winding down the Active Management of Labor Study3 that was designed to try to replicate what had gone on at the Dublin Maternity Hospital,4 and if I’m remembering correctly, one of the remarkable things about that is that in Dublin, there were virtually no C-sections in the second stage. And so people assumed that while they were more aggressive with forceps, the operative vaginal delivery rate was no different between Brigham and Women’s Hospital and the Dublin Maternity Hospital. And so there needed to be another explanation.
