In 1937, the percentage of deliveries done via C-section at Boston City Hospital was 3%. In 2005, national rates of C-section are slightly more than 30%. In 1937, 6% of primiparous women - women having their first baby - who delivered via C-section died following the surgery. Fortunately, the mortality rate following C-section now is much less. I'm not sure of the exact number, but it's something like one in every several thousand sections. The authors suggest some reasons for the increased rate of C-sections, including a decline in the number of vaginal breech births - a C-section is nearly always done now in such deliveries; an increased number of multiple gestations (twins and triplets, etc.); decreased numbers of forceps and vacuum deliveries; and lower rates of vaginal births in women who previously had C-sections.
Anecdotally, fifteen to twenty years ago there seemed to be a big emphasis among obstetricians on trying to decrease the rates of cesarean sections, and I simply don't see that attitude any more. I don't blame my obstetric colleagues, because they have a pretty tough job. I just think that with newer data showing harm after breech vaginal deliveries and vaginal deliveries following C-sections, a relatively high rate of sections is simply accepted as a cost of decreasing neonatal injuries.
Speaking of neonates, the second article I noticed is in the March Journal of Pediatrics. The article, by a group from Italy, shows that the incidence of pneumothorax - a collapsed lung - in neonates is greater following cesarean sections than it is following vaginal deliveries. Also, in term babies delivered via C-section, the incidence of pneumothorax is greatest for babies born at 37 weeks, less for those born at 38 weeks, and even less for those born at 39 weeks. None of this will greatly surprise neonatologists. We can pretty much tell you from personal experience that the chance of a baby having respiratory problems is greatest following a C-section not preceded by labor, less if the C-section had labor preceding it, and even less following vaginal birth; and if born via C-section, the more mature the baby is, without going post-term, the better his chances of not having breathing problems.
Tough questions regarding C-sections come when a very premature baby, say at 23 to 24 weeks, needs to be delivered. Given the baby's lower chances of survival, is it justified to put the mother through the greater risk of a C-section versus vaginal delivery if the baby's condition warrants immediate delivery? I'll let my OB friends make that call - most of them seem willing to do C-sections at 24 weeks gestation but less so at 23 weeks - but would like to point out that when 30% of all deliveries are done via C-section, nearly every woman knows one or more persons who have had one and did fine, so it's tough to convince those moms of the added risks of a C-section versus vaginal delivery. I know, a C-section at 23 weeks has more risks than one at term, but still, the moms will usually gladly accept a greater risk to themselves if it means any advantage for their child.