Does C-section increase the rate of neonatal death?

It is a potentially devastating indictment of the rising C-section rate. Most midwifery and “natural” childbirth websites claim that elective C-section triples the rate of neonatal mortality. Mainstream web sites like Feministing.com, and newspapers like The New York Times have repeated the claim. There’s just one problem. It’s not true.

The claim originated with the paper Infant and Neonatal Mortality for Primary Cesarean and Vaginal Births to Women with “No Indicated Risk,” United States, 1998–2001 Birth Cohorts, MacDorman et al, Birth Volume 33 Page 175, September 2006. According to the authors:

Neonatal mortality rates were higher among infants delivered by cesarean section (1.77 per 1,000 live births) than for those delivered vaginally (0.62). The magnitude of this difference was reduced only moderately on statistical adjustment for demographic and medical factors, and when deaths due to congenital malformations and events with Apgar scores less than 4 were excluded. The cesarean/vaginal mortality differential was widespread, and not confined to a few causes of death. Conclusions: Understanding the causes of these differentials is important, given the rapid growth in the number of primary cesareans without a reported medical indication.

The implication, of course, is C-sections done without a medical indication raises the risk of neonatal death by a factor of three. The entire study hinges on a critical detail. Are women with “no indicated risk” really women who have no risk factors? The answer is a resounding no.

Since birth certificates are such an important source for research information, they have been repeatedly studied for accuracy. Birth certificates are highly accurate for administrative data like parents’ names or numerical data like weight or Apgar scores. It is well known, however, that they are highly inaccurate when it comes to listing complications.
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