In late September of this year, researchers in the US dropped a bombshell onto the cosy world of obstetrics.
After analyzing the records of nearly six million births, they advised that mothers should think twice before choosing a caesarean section (CS) over a natural birth.
Quite simply, an artificial surgical delivery could be putting the life of the newborn at risk. What the stark American statistics revealed was that caesarean babies are almost three times more likely to die within their first month of life than naturally delivered babies (Birth, 2006; 33: 175).
And yet, caesarean births ('C-sections' in medico-speak) have never been more popular. For an increasing number of mothers-to-be, the ready availability of CS has meant that the trauma of giving birth can be leapfrogged. The old Biblical curse of having to endure a painful labour is exorcisable-birth can be as simple as having an appendix removed.
Take this passage from a popular American book on pregnancy: "With a scheduled caesarean sec-tion, you and your doctor have agreed to a time at which you will enter the hospital in a fairly calm and leisurely fashion, and he or she will extract your baby through a small slit at the top of your pubic hair. There are a lot of reasons to schedule a C-section, [including] to maintain the vaginal tone of a teenager." (Iovine V. The Girlfriends' Guide to Pregnancy. Pocket Books, 1995).
What is a caesarean? For centuries, the classical CS operation has involved a long surgical incision made either vertically or horizontally across the centre of the abdomen, cutting through to the womb below. However, the operation is fraught with complications-not least of which is huge blood loss-and is now rarely performed for this reason. However, the modern CS entails a much smaller incision (a mere four to five inches across) low down on the abdomen, just below the top of the pubic hair-the resulting scar thus conveniently invisible even under a bikini.
The term 'caesarean' is popularly thought to be named after the Roman leader Julius Caesar who was allegedly born that way. However, doctors now think that story is unlikely, as the operation would almost certainly have killed his mother (given the medicine of the day)-and yet, historical records show that she was still alive after he reached adulthood.
A more plausible derivation is from the term lex caesarea, a Roman law passed during Caesar's reign decreeing that, if a mother was dying during childbirth, the baby could be surgically removed to save its life.
In the US, 29.1 per cent of all births are now delivered by CS, according to 2004 statistics. And the British figure is not far behind at 21.6 per cent. Of these, almost half (8.9 per cent) are 'elective'-in other words, chosen by the mother, not by the doctor because of a medical emergency (BMJ, 2004; 328: 1399). Why so many? After all, the UK does not have the same financial or litigious pressures as has the US.
The answer appears to be that some women (anecdotally, the British upper classes) consider normal births too traumatic, inconvenient, distasteful and disfiguring to put up with-an attitude memorably summarized as 'too posh to push'.
There is some evidence for this.
A research group at Imperial College in London recently collated the UK's CS data according to social class, and found that elective CS operations are not so much the province of the top social classes, but rather more a no-go area for the lower classes-as they put it: "not a case of too posh to push", but "too proletarian for a caesar-ean" (BMJ, 2004; 328: 1399).
Although fear and distaste for labour may play a part, another is that doctors often pressgang women into having 'just-in-case' caesareans for dubious reasons, such as the fact that the baby is large, is slightly overdue or in a breech position (see box, page 6).
CS allows the doctor to do 'daylight obstetrics', obviating the need to hang around for a woman to deliver her baby, often in the middle of the night (birth rates peak at about 4 o'clock in the morning). While labour can last for hours, a typical CS is usually done and dusted in less than 40 minutes.
Money's a factor, too. In the private American health system, doctors and hospitals find CS more profitable than natural births, according to a World Health Organization (WHO) report. "In the USA, the profit motive explains hospital-specific CS rates that are high even by US standards" (Stephenson P. International Differences in the Use of Obstetrical Interventions. Copenhagen: WHO European Regional Office, 1992). That report came out 15 years ago-and CS rates have soared since then.
Another factor is litigation. "Some caesareans are clear medical necessities," says Professor Joel Evans of the Albert Einstein College in New York, "but others lie in a gray area, where there are other possible medically appropriate options. Now, more and more physicians find it easier to follow the growing trend of just go ahead and do it, avoid a lawsuit."
Advances in surgery and anesthesia have made an operation that was almost always fatal as recently as the mid-19th century a routine one 150 years later. And yet, CS is still not to be undertaken lightly. The most recent mortality figures come from a huge study on over 150,000 elective CS operations in Britain, and shows that mothers run nearly three times the risk of dying from a CS than from a natural delivery (Lancet, 1999; 354: 776).
Other risks to the mother include the potential problems associated with any major abdominal surgery-anesthesia accidents, damage to blood vessels, and injury to the bladder, uterus or other organs. Also, perhaps surpris-ingly, CS comes with a much higher risk of infection than natural birth (Cochrane Database Syst Rev, 2002; 3: CD000933). Other, longer-term risks include possible decreased fertility, ectopic pregnancy and miscarriage (Lancet, 2003; 362: 1779-84).
But it's the newly discovered risk to the newborn child that has so shocked obstetricians. The report recently published in a peer-reviewed journal was a four year survey of all CS operations performed in the US from 1998 to 2001. The researchers, led by Dr Marian MacDorman of the Centers for Disease Control and Prevention (CDC), studied the records of nearly 5.8 million live births and almost 12,000 subsequent infant deaths, and found a nearly three-fold increase in the death rates
of elective CS babies within four weeks of birth. The figures are relatively small, but nevertheless highly significant. While there were only 62 deaths per 100,000 natural births, a staggering 177 babies died within a few weeks of CS surgery (Birth, 2006; 33: 175).
Doctors have been anecdotally aware of a higher risk with CS for years, but have tended to explain it away because CSs are usually an emergency procedure, caused by a problem with the birth anyway. However, MacDorman's study has removed this confounding factor by analyzing the records only of women who had had no compli-cations whatever with either kind of delivery. This meant that the difference in the babies' death rates could only have been due to the delivery method itself.
In short, caesareans can be lethal-but why?
The risk to the mother can be explained by the fact that it's a major abdominal operation, but why should the baby itself suffer any harm? Well, there is evidence that the baby may sustain "brachial plexus injury, damage to soft tissues, fractures, lacerations, and entrapment of fetal head followed by intracranial haemorrhage" during CS (Cox JP. ICEA Review: Delivery Alternatives in the Term Breech Pregnancy. November, 1988). But those 'complications' are relatively rare, so it's unlikely to be the whole answer.
Natural birth benefits
Another way to explain the new MacDorman data is to turn the question on its head, and ask not what's wrong with CS, but what's so right about a natural birth?
One suggestion is that natural vaginal delivery releases hormones such as prolactin which promote healthy lung functioning. In fact, CS babies are known to have impaired respiration compared with non-CS babies (Arch Dis Child 1997; 77: F237-8). Another factor may be the sheer physical pressure on the baby when being expelled through a narrow opening. This, too, may improve lung function by pushing fluid from the lungs and preparing the child for immediate air-breathing.
Support for these theories has come from studies that have found a link between CS and later respiratory disorders-in particular, asthma. A recent German survey discovered that CS-born children have higher rates of asthma (and, incidentally, more food allergies) up to age two than naturally born babies (Pediatr Allergy Immunol, 2004; 15: 48-54)-a pattern that continues into adulthood. Astonishingly, even as much as a whole generation later, the long-term effects of CS still show up. Finnish researchers have found over three times more cases of asthma in CS-delivered 31-year-olds (J Allergy Clin Immunol, 2001; 107: 732-3).
Osteopaths believe natural labour may have other, less quan-tifiable effects. Some claim that the compression of the baby's body down the birth canal helps kick-start the natural maturation of infant reflexes, allowing proper neural development to take place. On the other hand, compression of the skull may also cause problems such as colic and irritability.
Avant-garde gynaecologists such as the famous water-birth pioneer Dr Michel Odent are convinced that natural labour has more tangible benefits. Breastfeeding, for example, is often easier after a natural birth, says Odent, possibly because of the better psychological bonding between mother and child after a natural delivery.
There may be two main reasons for this. First, CS is a much more medicalized procedure than a natural birth and, as such, it distances the mother from her newborn. Second, the very act of giving birth through the vagina stimulates the production of oxytocin-dubbed 'the love hor-mone' by Odent. This hormone is known to play a primary role throughout the whole birthing process, as it floods the mother's brain with powerful signals 'telling her' to care for her infant (Odent M. The Caesarean. London: Free Association Books, 2004).
Once a Caesar . . .
Another frequently cited reason for shunning a CS is to avoid another one for a later pregnancy. There's an old medical maxim that says 'Once a Caesar, always a Caesar' as, traditionally, it is believed that a CS scar weakens the mother's abdomen, and so makes it more vulnerable to the pressure of a subsequent normal delivery.
This so-called VBAC (vaginal birth after caesarean) issue remains a hotly debated topic in obstetric circles. In the US, for example, over 300 hospitals have reportedly now banned VBACs over fears of malpractice suits. As a result, VBAC rates have plummeted. However, that trend is being challenged by a few vociferous American women pressure groups. They claim that doctors who insist on repeat CSs are denying women the right to have a natural birth-which in any case, they say, is just as safe as a caesarean.
Which side is right? Unfor-tunately, no one really knows. Two exhaustive reviews of the clinical data, one going back as far as 40 years, have proved inconclusive, partly because good-quality data are lacking (Aust NZ J Obstet Gynaecol, 2004; 44: 387-91; Oregon Health & Science University Publication No 03-E018, March 2003). An older study of more than 5000 deliveries found not one maternal death (Obstet Gynaecol, 1982; 59: 135).
There is, however, one aspect of the CS issue where there's some-what broader agreement. If labour is difficult and the life of the mother or child is immediately under threat, an emergency caesarean is generally considered the safest option.
The most common emergency situation is with so-called breech births-where the baby has its bottom facing the birth canal rather than being head downwards. In the days before anesthesia and surgery, all manner of complex devices were invented to extract the baby from this difficult position-one that is potentially dangerous to both the mother and infant. Some doctors have also attempted to solve the problem by developing techniques of turning the baby in the womb from the outside. More recently, the trend in these cases has been to perform a CS rather than risk a natural delivery.
But here again, this issue has divided the world of obstetrics, with some arguing passionately that CS is not necessarily the safer option for breech-presenting babies.
In an effort to resolve the controversy, Canadian researchers set up a huge international trial, involving over 2000 breech births in 121 maternity units around the world. Roughly half of the babies were delivered naturally, with the other half by CS. Although the absolute risks to the infants were relatively small in both cases, the differences appeared to be clear-cut: whereas 1.6 per cent of the breech babies either died or were damaged by the CS operation, that figure leapt to 5 per cent for those born without it. In both scenarios, the mothers fared equally well (Lancet, 2000; 356: 1375-83).
This result should have meant 'case closed' in favour of CS for breech deliveries-but not so. A few years later, South African researchers collated fresh inter-national birth data which showed that the benefit of CS to the infant had to be weighed against a modest increase in danger to the mother (Cochrane Database Syst Rev, 2003; 3: CD000166). This revised stance was again confirmed by Dutch doctors who agreed that CS was better for the child, but not necessarily for the mother (Br J Obstet Gynaecol, 2003; 110: 604-9).
And yet, that conclusion is flatly contradicted by an earlier study from the UK. In 1987, after review-ing 10 years of experience of both methods, doctors at the Leeds University Hospital concluded that CS is less hazardous: ". . . vaginal delivery may be the more dangerous maternal option," they reported (J Perinat Med, 1987; 15: 531-43). Two very recent studies on the subject have only served to fuel the controversy. Last January, an Israeli expert published a stinging condemnation of the original Canadian review, complaining of "serious" flaws in its design and methods-and, not surprisingly, totally rubbishing its conclusions (Am J Obstet Gynecol, 2006; 194: 20-5). Three months later, a French report went further, questioning the whole rationale for opting for CS in breech births. In the right hands, it said, the records showed that natural breech births are just as safe as CS deliveries (Am J Obstet Gynecol, 2006; 194: 1002-11).
Improving the odds of a natural birth
- Supplements. Take a general multivitamin/mineral supplement and have levels of all nutrients, including folic acid, checked to avoid congenital abnormalities; abnormal babies are more likely to end up as breech babies.
- Stay upright and mobile. Walking has no known side-effects and is as effective as oxytocin for augmenting labour (Am J Obstet Gynecol, 1981; 139: 669-72). Women who walk, stand or sit upright during labour have shorter labours, use less pain relief and less augmentation than those who are supine and immobile (Enkin Metal. A Guide to Effective Care In Pregnancy and Childbirth: A Synopsis. Oxford University Press, 2000).
- Choose midwifery care. Studies show that midwifery care equals low caesarean rates. One survey of 84 free-standing birth centres in the US, staffed by midwives, reported an overall caesarean rate of 4.4 per cent (N Engl J Med, 1989; 321: 1804-11).
- Be patient. Some labours, especially first labours, are simply long. Women who have had a previous caesarean, especially one performed before a 4-cm dilation, may have long labours comparable to those of women having their first baby (Obstet Gynaecol, 1990; 75: 45-7).
- Opt for a doula (a midwife who cares for the mother from conception to birth). A slew of clinical studies have shown that they can reduce CS rates (J Womens Health Gend Based Med, 1999; 8: 1257-64). In addition, the presence of a doula (or trained birth companion) has been shown to cut the average length of labour by half-from 19.3 hours to just 8.8 hours (N Engl J Med, 1980; 303: 597-600).
- Consider having your baby at home-you're much more likely to then have a natural birth. Although home is often best, according to Michel Odent, other evidence show that even somewhere that's 'home-like' can also prevent caesareans (Cochrane Database Syst Rev, 2005; 1: CD000012). Some hospitals offer this option, often along with facilities such as birthing pools, which also potentially promote natural birthing (Birth, 1996; 23: 136-43).
- Avoid having an epidural during labour, as CSs are more common after administration of these analgesics/anesthetics (Clin Nurs Res, 1999; 8: 119-34)