The World Health Organization has said (and since reiterated — despite the latest spin-doctoring, which Science and Sensibility exposes) that no country or region should have more than 10-15% C-section rate, and that once above that rate, more mothers and babies are harmed rather than helped by this intervention. The rising maternal mortality rates in the United States (and perhaps other countries) seems to be corroborative evidence of that. So, when might it be a good thing? I can envision one scenario.
If an obstetrician were in practice with several midwives, and the midwives took care of all the normal (low-risk) women, while the high-risk cases were referred out to him, that might be an ideal situation. Assuming the midwives are not “medwives,” they should have low rates of interventions, including C-sections. However, the doctor, having a clientele composed strictly of high-risk women, would have a much higher rate of interventions. Of course, not all “high-risk” women will need C-sections, but the 10-15% figure of ideal C-section rate includes the normal mix of all risk levels of women — so low-risk women would probably need C-sections in the range of 2-5% (which is probably the rate among intended home-birthers), whereas higher-risk women may need C-sections higher than 15% of the time — perhaps 30%? Maybe higher, depending on the particular type of risk.
I have a hard time believing any obstetrician, except perhaps one who has only an ultra-high-risk clientele (and maybe not even then), can justify a C-section rate of 70%, but there are doctors who do have rates that high. Let’s see.
Let’s assume that it is our goal to have a 10-15% C-section rate across a normal mix of risk levels, and there are four midwives and one obstetrician in the practice, with the midwives seeing all the low-risk clients, and transferring all the high-risk ones to the OB. We’ll also assume that the patients are equally divided, so that all providers see the same percentage of clients — that would put the “high-risk” group at 20% of the average population. Assuming the midwives had a 5% C-section rate, the OB would have to have a 55% C-section rate for the practice average to be 15%; if the practice average were at 10%, then the doctor’s C-section rate would need to be 30%. [Out of 100 clients, 80 would be low-risk and see midwives, and for a 5% C-section rate would have 4 total C-sections; so 10% total C-section rate would be 10 women, and 15% would be 15; 10-4=6, 15-4=11. The OB would see 20 women, and would section 6-11 of them for 10-15% total.]
There is no single definition of “high risk,” however, and different providers might use different criteria; and some midwives may continue caring for some women who move into a “high risk category,” while other women may be transferred to doctors. The University of California at San Francisco said that only 6-8% of all pregnancies will have high risk complications, so I’ll use those numbers. [The numbers seem a little low — perhaps they’re only looking at women who ultimately have complications, not just those who are at higher risk of complications.] We’ll assume that instead of an even mix, the OB only sees 10% of all patients (perhaps some low-risk women just want an obstetrician, or they transfer some that they didn’t truly need to), while the midwives (with their 5% C-section rate) would see the remaining 90% — oddly enough, that’s about the reverse of the actual situation in the United States, with midwives seeing about 10% or less of all pregnant women, and obstetricians seeing about 90%. With a 5% C-section rate, 4.5 clients of midwives would have their baby through an abdominal incision (I’ll round it up to 5), so of the doctor’s 10 clients, he would have to have a C-section rate of 50-100%, in order to have a 10-15% C-section rate across the entire practice.
So, it could be possible for a doctor to have an ultra-high C-section rate, while still practicing evidence-based medicine. It’s just not very likely.
The figures I’ve played with above are, of course, only estimates and best guesses. Most obstetricians are not in the idealistic situation described above. (I know of none — do any of you know of such a practice, or such an obstetrician, who sees only high-risk women?) With 90% of the pregnant population seeing obstetricians, the average doctor is going to be seeing primarily low-risk clients. So why are their C-section rates so dad-blame high?? There are 4 millions live births in the United States every year, with a 31.7% C-section rate, or 1,268,000 babies born by C-section. Assuming there to be a “normal” mix of low- and high-risk patients (say, 92% and 8% respectively), and all high-risk patients have C-sections, that still only accounts for 320,000 births, with 948,000 C-sections being performed on low-risk patients. Even subtracting 5% low-risk women (200,000) who will end up with a necessary C-section, that still leaves about 750,000 C-sections to be accounted for. Somehow, I don’t think “maternal request C-sections” can account for all of that.
So, if your obstetrician has a clientele composed of primarily high-risk patients, and he has a high C-section rate, that might be understandable. But for the average obstetrician… not so much.