DEATTRIA MOSELY stands next to the white bassinet in her family's sparsely furnished living room, cradling her three-month-old son, Lemuel. Waking from a nap, Lemuel yawns, gurgles, then coos, drawing a smile from his mother. Just 18 months earlier, Ms. Mosely - a teen-age high-school dropout, had delivered a baby girl who lived only five hours. It was a personal tragedy for Deattria, and one that involved her in what United States health experts and children's advocates consider a national scandal: the high, and in some states increasing, rate of infant mortality.
According to UNICEF, in 1986 (the most recent year for which data are available) the US tied for 17th place in a ranking of countries based on infant-mortality rates - behind Japan, nearly all European countries, and Singapore - with 10 deaths per 1,000 live births.
In a similar 1985 ranking, the US white population fared slightly better, ranking 14th, but the US black population ranked 28th - with 19 deaths per 1,000 - behind Cuba, Bulgaria, and Costa Rica.
Health care experts say poverty, ignorance about prenatal care, and a dearth of maternal- and infant-health services all contribute to a US infant-mortality rate that is higher than those of most industrialized countries.
More broadly, many experts say the nation's attitude toward children - whether reflected in cutbacks this decade in funding for maternal- and infant-health services, or in expectant mothers' willingness to mix pregnancy and dangerous-substance abuse - is also an important factor.
``Children are just not a priority in this country,'' says Dana Hughes, a child-health specialist with the Children's Defense Fund in Washington. ``With an American culture that says families ought to do for themselves, there has never been a strong policy emphasizing children's needs.''
A recent Columbia University study of 75 countries showed that all but two - the US and South Africa - had a general structure of government policies setting standards for such matters as maternal leave and designed to support families with children.
Federal funding for maternal- and child-health programs and community health centers was cut at the outset of the Reagan administration. Although appropriations have ``crept back up'' in the past year or two, according to Hughes, ``it's hardly been enough to keep up with inflation.''
California, for example, has experienced a rise in premature and underweight babies. Both health experts and many local officials blame the problem on a decline in availability of prenatal care.
In Dallas, which in a recent ranking had the fifth-highest rate among US cities for black infant mortality and seventh-highest for all infants, officials point to a reduction in the number of clinics offering maternal care in the city's poor neighborhoods.
Compounding the effect of inaccessible services is the high incidence of teen-age pregnancies in these same neighborhoods. ``As long as we've got babies having babies, we're going to have lots of problems,'' says Paul Boumbulian, vice-president for strategic planning at Parkland Memorial Hospital in Dallas.
Although older adolescent girls are generally just as able physically as adult women to bear healthy children, other factors common among them - poor diets, lack of maturity, a desire to deny the pregnancy - can lead to complications at birth.
``Access to services and the ability to pay ... are real barriers to providing important preventive care,'' says Betsy Attel, vice-president of maternal and child health at Parkland, Dallas County's huge public hospital. Dr. Attel notes that 16 percent of the nearly 15,000 women who delivered at Parkland last year had no prenatal care whatever.
Nearly 10 percent of Parkland's newborns required admission to the hospital's special-care nursery, for stays that cost the county $4,000 on average.
Yet Attel says that, with studies showing $3 in savings for every $1 spent on preventive maternal care, state and county officials in Texas are beginning to put money into programs designed to reduce infant mortality. One such program, begun three years ago as part of the state's landmark indigent health-care program, is already reaching thousands of expectant mothers annually - including Deattria Mosely.
``[That program] has been very helpful, because it allowed me to see the doctor,'' Mosely says. ``It wouldn't have been possible otherwise, because we didn't have no money for it.''
Attel says there is no solid statewide evidence yet that the program has been effective, but she notes that women in Parkland's program have a lower percentage of infants entering the special-care nursery.
Yet Attel and others say the problem of infant mortality is much larger than a question of medical care, and will not be solved in hospitals and clinics.
``Until we do something about the environment these women and children reside in, the problem won't go away no matter how much medical care we dump out there,'' says Stephen Heartwell, director of maternal health and family planning for the University of Texas Southwestern Medical School here.
With that in mind, Dallas officials from the city, the county, and the county hospital district are beginning to work together to provide integrated, community-based health care that will eventually encompass issues such as nutrition, housing, and employment.
The method, termed community-oriented primary care and based on a World Health Organization model, is designed to ``reach beyond basic health needs,'' says Dr. Boumbulian.
One idea springing from that approach is a program called SPAN - Serving Pregnant Adolescents' Needs - that teaches pregnant adolescents how to care for their babies, and themselves, before and after delivery.
``Before I got pregnant I was eating a lot of junk food - sodas and chips,'' says Janie LeGree, a participant in SPAN. ``But they told me I need a better diet for the baby, so now I eat a lot of fruit and leafy green vegetables, which I hate. But I eat it anyway.''
An important impetus to Ms. LeGree's participation in SPAN was her mother, who lost a child six months after birth. ``Having had my own complications, I really encouraged her to go to prenatal,'' says Mrs. Thompson.
ODDLY, Hispanics in the US experience fewer infant deaths proportionately than either blacks or whites, even though their rate of poverty is higher and their access to services is presumably lower.
Some researchers believe that the kind of close family support Janie Thompson is getting, common among Hispanics, could be a factor. Others point out that Hispanic women are less likely to use tobacco, alcohol, or drugs, and that even cultural attitudes about children could be a factor.
``The Hispanic children are prized, they are literally considered gifts of God,'' says Parkland's Attel, who has worked in the two cultures. Hispanic mothers ``do whatever they have to to feed and care for their children.''
Studies also show that foreign-born Hispanic women - especially those from Mexico - experience fewer infant deaths than US-born Hispanics, suggesting to some experts that the rice-and-bean diet and close-knit family life among Mexican poor is better for maternal health than the conditions that characterize US poverty.
Based on those findings, health-care officials in Arizona are using older Hispanic women to help teach prenatal care to younger Hispanics. ``It's an effort to reestablish the ties that existed more typically in the Mexican culture, and it seems to be working very well,'' says Marianne Remy, program coordinator at the University of Arizona rural health office in Tucson, Ariz.
In Dallas, some health-care officials say they are seeing evidence of greater concern for infant health in the US. Some increased federal funding for prenatal care and new state programs are part of the evidence they cite, as is the emphasis being placed on the issue by the Children's Defense Fund and such national leaders as Sens. Bill Bradley (D) of New Jersey and Lloyd Bentsen (D) of Texas.
``Hopefully we're moving in the right direction on this,'' says Dr. Heartwell of Southwestern Medical. ``But when you're 17th in the world, you've got a ways to go.''