The so-called system for providing prenatal care to women on welfare sounds as if it was designed to get pregnant women into buses rather than into medical clinics.

First, a woman must go to one office to apply for Medicaid. Then she must go to a clinic for a pregnancy test. Then she must go to another location for prenatal care. Then she must travel to still another clinic for immunizations.With such a patchwork of uncoordinated programs, no wonder that one in three pregnant women, an estimated 3 million a year, gets inadequate prenatal care.

No wonder, too, that so many babies are born with low birthweight, a major contributor to infant death that could be prevented with early and comprehensive prenatal care.

This week a 16-member federal commission came up with a solution that makes sense. The National Commission to Prevent Infant Mortality, established by Congress in 1987, wants Washington to set up what would amount to a "one-stop shopping" system where a variety of related government services for needy pregnant women could be provided at a single location.

It may not be easy to get Congress to go along with such a program on a full-scale basis without first trying out one-stop clinics in a few selected cities. But, in view of the success of the one-stop concept in private enterprise, it's hard to imagine such experiments flopping.

Let's get rid of the needless layers of bureaucracy. Poor women should not be forced to run an obstacle course to get prenatal and other health care.