Bottom line: Planned homebirth has a twenty-fold increased risk of intrapartum death when compared with planned hospital birth.
Birth outcomes of planned home births in Missouri: A Population-Based Study by Chang and Macones published in the American Journal of Perinatology in August 2011 is notable for careful methodology.
.. We obtained data from the Missouri live birth and fetal death files that have been linked together by the Missouri Department of Health and Senior Services… The Missouri vital record system is considered very reliable and has been adopted as a “gold standard” to validate other vital statistic datasets in the United States…
The authors conclude:
Our analysis demonstrates cause of concern about safety of planned home births attended by non-CNMs and physician/CNMs. The results of our study suggest that planned home births are associated with increased likelihood of intrapartum fetal death and newborn seizures, despite the fact that the lowest risk women choose this birthing option.
In fact, they found that homebirth had TWENTY times the risk of intrapartum death as hospital birth. Not only that, but as is the case with most homebirth studies, this study could not separate out home birth transfers from the hospital birth group. Therefore, the study likely underestimates the increased risk that homebirth represents.
For more discussion of this study, see The Skeptical OB.