Janssen retracts conclusion of her 2002 CMAJ homebirth study

Patricia Janssen's study Outcomes of Planned Home Births vs Planned Hospital Births in British Columbia (CMAJ, 2002) is often cited as showing that homebirth is as safe as hospital birth. I have criticized the study on several occasions in the past. Not surprisingly, I am not alone. The Canadian Medical Association Journal published 7 letters to the editor critical of the study's statistical methods and the conclusions of the study, specifically the fact that the homebirth and hospital groups were not the same and that the homebirth group had 2 perinatal deaths and the hospital group had none. The CMAJ offered Janssen an opportunity to reply to her critics. Her response includes the following:

Although we tried to ensure that comparison groups met eligibility criteria for home birth, women who choose home birth differ from those who select hospital birth in both measurable and unmeasurable ways...

Furthermore:

The purpose of our study was not to determine which method of care was better, home vs. hospital, [my emphasis] but rather to assess whether, at the 2-year interval, home birth was safe enough to continue to be offered as a choice for women in the context of ongoing evaluation.

And:

The small number of adverse outcomes among an essentially healthy population of women limits the power of a single study to make valid conclusions.

So Dr. Janssen herself, the lead author of the study, acknowledged in response to criticism that the homebirth group was NOT equivalent to the hospital group in risk, that the study was NOT to determine whether homebirth is as safe as hospital birth and that the study is limited in its ability to make VALID conclusions. Therefore, homebirth advocates should not be citing it as a study that shows homebirth to be as safe as hospital birth.


This piece first appeared on Homebirth Debate in June 2006.