Planned home birth has been considered by some to be consistent with professional responsibility in patient care. This article critically assesses the ethical and scientific justification for this view and shows it to be unjustified. We critically assess recent statements by professional associations of obstetricians, one that sanctions and one that endorses planned home birth. We base our critical appraisal on the professional responsibility model of obstetric ethics, which is based on the ethical concept of medicine from the Scottish and English Enlightenments of the 18th century. Our critical assessment supports the following conclusions. Because of its significantly increased, preventable perinatal risks, planned home birth in the United States is not clinically or ethically benign. Attending planned home birth, no matter one's training or experience, is not acting in a professional capacity, because this role preventably results in clinically unnecessary and therefore clinically unacceptable perinatal risk. It is therefore not consistent with the ethical concept of medicine as a profession for any attendant to planned home birth to represent himself or herself as a "professional." Obstetric healthcare associations should neither sanction nor endorse planned home birth. Instead, these associations should recommend against planned home birth. Obstetric healthcare professionals should respond to expressions of interest in planned home birth by pregnant women by informing them that it incurs significantly increased, preventable perinatal risks, by recommending strongly against planned home birth, and by recommending strongly for planned hospital birth. Obstetric healthcare professionals should routinely provide excellent obstetric care to all women transferred to the hospital from a planned home birth.The professional responsibility model of obstetric ethics requires obstetricians to address and remedy legitimate dissatisfaction with some hospital settings and address patients' concerns about excessive interventions. Creating a sustained culture of comprehensive safety, which cannot be achieved in planned home birth, informed by compassionate and respectful treatment of pregnant women, should be a primary focus of professional obstetric responsibility.