Smoking is frequently presented as being particularly problematic when the smoker is a pregnant woman because of the potential harm to the future child. This premise is used to justify targeting pregnant women with a unique approach to smoking cessation including policies such as the routine testing of all pregnant women for carbon monoxide at every antenatal appointment. This paper examines the evidence that such policies are justified by the aim of harm prevention and argues that targeting pregnant women in (...) this way is likely to do more harm than good. Routine carbon monoxide testing is particularly problematic as it sends a message to pregnant women that they cannot be trusted either to truthfully answer questions as to whether or not they smoke, or to make decisions in the best interests of themselves and their future children in the way that non-pregnant individuals are. Further, if the aim is to reduce rates of prenatal harm, the evidence suggests that adopting a supportive and empowering approach to prenatal care is the most effective way to achieve this, something that the current policies aimed at pregnant women are in conflict with. (shrink)