 When a pregnant woman is decisionally impaired or incompetent, however, there are extra layers of ethical complexity to contend with, because her treatment typically affects not only her, but also her child to-be. The developing fetus clearly has welfare (or at least future welfare) but no capacity for autonomous choice, and we have no formula for combining its interests and moral claims with those of the mother. For extra complication, the well-being of the child to-be is typically not independent of the well-being of its mother. Further ethical issues may arise in cases where, prior to serious decision impairment (due, for example, to massive brain injury or brain death), the pregnant woman has autonomously expressed her preference to continue to gestate and give birth. In such cases, ethicists at both the clinical and policy-making level may face questions about how to respect the pregnant woman's autonomy while balancing concerns for the potential child. They may be required to consider how external factors such as available caregivers for the potential child may factor into the possibility and desirability of going forward with the pregnancy. Thus doctors must balance autonomy-based and beneficence-based obligations to the pregnant woman, along with beneficence-based obligations to the fetus (e.g. Coverdale et al. 2004). When a pregnant woman is decisionally competent, health care practitioners and ethicists strongly privilege her right to make final treatment decisions in complicated cases where her interests may conflict with those of her future child (although see section 3.2 below). Moreover, the fetus generally has no legal standing that would allow its interest to override the pregnant woman's interest (Sperling 2006). But when the pregnant woman has diminished or no autonomy, the situation is murkier.