Have any data? I seriously doubt that infant mortality in the US is substantially caused by inaccessibility to prenatal care.
From a CBO report (http://www.cbo.gov/doc.cfm?index=6219&type=0)
Federal and state initiatives to lower infant mortality rates have focused on strategies to reduce financial barriers that limit access to prenatal care and on strategies to expand the supply of prenatal care services available to poor pregnant women. The relative advantages and disadvantages of these and other policies to reduce low birthweight and infant mortality are the focus of considerable debate. Recent expansions of the Medicaid program are enabling more low-income children and pregnant women to obtain the health care that they need. Being eligible for Medicaid does not necessarily guarantee access to care, however, especially in areas where providers are in short supply. Hence, federal programs that provide direct support for maternal and child health services and primary care for low-income populations are also important. Some policy researchers believe, moreover, that the scope of strategies to reduce infant mortality should be broadened from a relatively narrow focus on pregnancy care to the more general issue of how to improve the health status of poor women and their families.
The CDC also concludes that the primary cause for infant mortality is low birth weights:
http://www.hhs.gov/asl/testify/t970313a.html
The problem is a largely a function of drug abuse and addictions. That's been widely documented.
Have any data? | 
