New ACOG opinion on planned homebirth

No surprises here. ACOG looked over the scientific evidence once again and found that it still shows that homebirth increases the risk of neonatal death.

The ACOG practice bulletin, Committee Opinion No. 476: Planned Home Birth appears in the February issue of Obstetrics and Gynecology. The Committee notes that many of the existing scientific papers are of poor quality, and almost all are observational:

Observational studies of planned home birth often are limited by methodological problems, including small sample sizes (Wiegers 1996, Ackermann-Liebrich 1996, Davies 1996, Janssen 2002); lack of an appropriate control group (Woodcock 1995, Anderson 1995, Murphy 1998, Johnson and Daviss 2005); reliance on birth certificate data with inherent ascertainment problems (Wax Maternal and newborn morbidity by birth facility among selected United States 2006 low-risk births 2010, Pang 2002); ascertainment relying on voluntary submission of data or self-reporting (Wiegers 1996, Anderson 1995, Johnson and Daviss 2005, Lindren 2008); a limited ability to accurately distinguish between planned and unplanned home births (Pang 2002, Mori 2008); variation in the skill, training, and certification of the birth attendant (Johnson and Daviss 2005, Pang 2002, Scramm 1978); and an inability to account for and accurately attribute adverse outcomes associated with antepartum or intrapartum transfers (Ackermann-Liebrich 1996, Pang 2002, Parratt 2002).

Then they turn to the most recent Wax study (Home versus hospital birth—process and outcome 2010):

… Although perinatal mortality rates were similar among planned home births and planned hospital births, planned home births were associated with a twofold-increased risk of neonatal death. When limited to only nonanomalous newborns, the increased risk of neonatal death was even higher––almost threefold higher in planned home births. These results did not change when the investigators performed sensitivity analyses excluding older studies or poorer quality studies. No maternal deaths were reported among 10,977 planned home births. When compared with planned hospital births, planned home births are associated with fewer maternal interventions …

They emphasize that all the existing scientific studies that show that homebirth is as safe as hospital birth comes from other countries that have strict selection criteria, dedicated transport systems, and highly trained midwives.

In summary:

… Women inquiring about planned home birth should be informed of its risks and benefits based on recent evidence. Specifically, they should be informed that although the absolute risk may be low, planned home birth is associated with a twofold to threefold increased risk of neonatal death when compared with planned hospital birth. Importantly, women should be informed that the appropriate selection of candidates for home birth; the availability of a certified nurse–midwife, certified midwife, or physician practicing within an integrated and regulated health system; ready access to consultation; and assurance of safe and timely transport to nearby hospitals are critical to reducing perinatal mortality rates and achieving favorable home birth outcomes.

Anyone who has been following this blog will not be surprised since I’ve written about almost all of these studies and pointed out that with the exception on the recent Dutch and Canadian studies (de Jonge 2010, Janssen 2009), there are no properly done studies that show that homebirth is safe. With the exception of the most recent Dutch and Canadian studies, all the existing studies that claim to show that homebirth is safe suffer from serious methodological flaws that render their conclusions invalid.

Although the Committee does not address this issue, recent data from The Netherlands suggests that the results of the de Jonge study are also in question. There may be no difference in mortality rate of midwife attended hospital and homebirth, but obstetricians have better outcomes in hospitals, even when caring for high risk patients, putting the safety of all midwife attended births (hospital or home) in doubt.

I wish the Committee had not place such reliance on the most recent Wax study, because as I wrote when it was released, it’s not a great study. No doubt American homebirth advocates will leap on this to discredit the Committee report, but that’s merely an attempt to divert attention from the key points which are indisputable:

There is not a single study that shows that American homebirth is as safe as hospital birth. All of them suffer from serious methodological flaws, particularly the use of inappropriate control groups designed to make the homebirth outcomes look better by comparison.

The only places where homebirth might potentially be as safe as hospital birth is The Netherlands and Canada, both of which have strict eligibility criteria, dedicated transport systems and highly trained midwives. Of these three criteria, American homebirth lacks ALL of them. And, as I pointed out above, the meaning of the Dutch results are now in doubt since the mortality rates of all midwife attended births are higher than the mortality rates for physician attended hospital births.

So homebirth advocates can jump up and down about the inclusion of the Wax study, but that doesn’t change the basic facts. There is NO evidence to show that American homebirth is safe, and a great deal of evidence to suggest that it is not.