Saturday, 11 April 2015

The WHO Recommended Caesarean Section Rate (2015 Edition)

Yesterday the World Health Organisation (WHO) issued a statement about Caesarean sections- the title was:

Caesarean sections should only be performed when medically necessary

This was, of course, picked up by the press, with The Guardian pretty much copy-pasting the headline. So, does the WHO have some striking new evidence that there are far too many unnecessary C sections going on and it's endangering women and babies?

Well, no.

The statement comes with the publication of an article in the medical journal The Lancet. This looked at two studies into Caesarean section rates in 21 countries around the world. It found that overall the C- section rate was increasing everywhere (other than Japan for some reason). One of the main observations was that in countries where the Caesarean rate had been very low, maternal and infant mortality dropped as that rate rose towards 10%.  Here's a quote from the press release:

“These conclusions highlight the value of caesarean section in saving the lives of mothers and newborns,” says Dr Marleen Temmerman, Director of WHO’s Department of Reproductive Health and Research. “They also illustrate how important it is to ensure a caesarean section is provided to the women in need - and to not just focus on achieving any specific rate.”

But isn't there a WHO recommended C section rate? 

I've lost count of how many times on this blog I've used the phrase:

There is no WHO recommended caesarean section rate!!!

It is a much loved "fact" dragged up by every journalist writing anything about Cesareans (and in the press release and Guardian article) that the WHO recommends all countries should aim for a C section rate no higher than 10- 15%. Much less than in many developed countries including the UK and USA. It's true that the WHO used to recommend this, but they quietly dropped that in 2010 after they admitted the figure was based on no real evidence. It pretty much just seemed like a good enough number to someone so he went with it.

This hasn't stopped journalists continuing to drag it out at every opportunity though. Want to say women are choosing C sections because they are too posh to push, because they think it's an easy option, or because they are worried about their sex lives? Drag out that 15% figure to show how unnecessary all those caesareans are. Want to say that all these surgical deliveries are making babies stupid or fat  or costing the NHS a fortune? Be sure to mention that the WHO thinks a lot of C section mums are just being selfish!

So what does this new study really tell us?

Rather than setting a maximum C section rate, all this study can actually do is set a minimum. It shows that when a country's caesarean rate is below 10% then women and children will die needlessly. It also found that that once the C section rate got above 10% there was no further decrease in maternal or infant mortality. However, that doesn't necessarily mean that 10% is the optimum number (as suggested by the Guardian). The Lancet team only had information on mortality but death isn't the only possible serious outcome of a difficult birth. My family knows first hand the life long effects of a baby being deprived of oxygen during a difficult birth and, while it's almost unheard of in countries with good access to modern medicine, there are many women around the world living with horrendous obstetric fistulas. Is a 10% C section rate enough to prevent these? We simply do not have the data and without it, setting an arbitrary target figure is potentially very harmful. Which is why the press release, the Lancet article and this interview with one of the authors all make the point that the focus should be on ensuring every women who needs a caesarean has access to one and not on achieving some specific national figure.

But all this must of course be balanced against the risks of potentially unnecessary major surgery. The paper doesn't tell us anything new about these but the press release makes some general comments about risks and also highlights the lack of data on the social and psychological effects of a mother having a caesarean as well as the cost implications. The latter being particularly important for weak health systems where increasing the number of C sections draws resources away from other vital services.

The WHO has a very difficult job here. It is, after all, the WORLD Health Organisation and, as with so many health issues, there is enormous variation in the caesarean rate around the world. This is evident in the data from the 21 countries in this report. Among the poorest, C section rates are generally low, in Niger the rate rose from 5.3 - 9.8% over the period covered. In some of the wealthier parts of central and south America the C section rate is very high. In Mexico, by the end of the study period, it had reached 47.5%. Clearly not all of those Mexican C sections will have saved a life or prevented long term harm and I've heard from women in other countries with very high C section rates who felt they were coerced or forced into the surgery without a good reason. I have no doubt that this is wrong and should be acted on. But at the other end of the scale the WHO is also dealing with countries where women and babies die because of too few C sections. We simply don't have the evidence to set an optimum caesarean section rate that applies to every country in the world.

The Lancet review seems reasonably useful. It looked at a variety of factors and how they influenced C section rates in 21 quite varied countries (although I notice that no European countries were in the list). But I find the WHO statement and the Guardian regurgitation of it troubling; if Caesareans should only be done when medically necessary, then how to we define "medically necessary"? When the risk of someone dying is 50%? 10%? 0.001%?  Is a C section "medically necessary" if it won't save a life but will prevent a long term disability? What about a minor short term problem? What if the medical need isn't physical? Vaginal birth with all the attendant examinations and indignities can have serious mental health implications for women who've experienced sexual abuse. Then there are the women who've already had traumatic births or who are just plain scared.

That's a lot of questions and the Lancet publication can not possibly answer them. It doesn't even try to. So I find it worrying and bizarre that an organisation as important and influential as the WHO should extrapolate so wildly from a specific and limited data set. It looks like an attempt to shoe horn in something controversial in order to gain column inches. If so it's been successful.

But that still leaves me with another question - even if we could define and predict which Caesareans are medically necessary - should they be the only kind?

Don't get me wrong there are some pretty major downsides to surgical birth. It may avoid the pain of labour but the recovery can be long and agonising and it's major surgery. Things can go wrong. But according to NICE (the UK National Institute for Health and Care Excellence) the overall risks of caesarean section aren't much greater than for vaginal birth. It recommends that if a woman with no medical indication wants a C section she should receive counselling to explore her reasons but if she still wants a Caesarean birth she should get one.

In the UK where most of us have the luxury of taking it for granted that we and our babies will survive childbirth this seems like a reasonable position. I've had two caesareans, the second was my choice but I wouldn't recommend it to anyone with a good chance of a straightforward vaginal birth. However,  It's not for me or anyone else to make that decision about another woman's body. I don't think it's a great idea to have a C section without a pretty good reason. I really don't think it's sensible to have a home birth after multiple caesareans but women do make these choices and so long as she has made it herself, based on accurate information, then ultimately it's her body her choice. 

It's also worth remembering that all these percentages are describing national averages. They can say nothing about any of the scenarios an individual woman may face. Just because your country has a worryingly high C section rate, it doesn't mean your placenta previa didn't really require surgery. Just because your country's rate is so low it's costing lives it doesn't mean you won't have a straightforward natural birth.

There is no WHO recommended caesarean section rate and there shouldn't be. The Lancet article demonstrates this but the media have once again twisted the limited conclusions of a piece of research into an opportunity to attack women's bodily autonomy. Bizarrely in this case, aided by a WHO press release.

Statistics are useful and interesting for those in the relevant field. Numerical targets may or may not be helpful at the national level. But individual mothers and babies are far more important than any numbers generated from them.

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