Black infant mortality risks studied.

Black infant mortality risks studied

Despite some impressive technological advances in the care of underweight infants, black infants in the United States still are twice as likely as white infants to die during their first year. Two recent studies reported in the Sept. 17 NEW ENGLAND JOURNAL OF MEDICINE have refined the search for the cause of this disparity by focusing on premature births and low-birthweight infants. Previous studies had found that infant mortality is related to premature birth or birthweight.

Researchers at Brigham and Women's Hospital, Harvard School of Public Health and the Harvard Community Health Plan of Boston interviewed 1,365 black women and 7,538 white women who had babies at Boston Hospital for Women between 1977 and 1980. Medical records were reviewed, as were known socioeconomic risk factors. The scientists found that, among the possible medical factors, only the hematocrit level "accounts for a substantial portion of the increased risk for premature births among blacks.' Hematocrit is the percentage of red cells in the blood. The authors point out that a low hematocrit may mean that the fetus is not receiving adequate oxygen, or that the mother may be suffering from a condition like poor nutrition.

Nonmedical risk factors examined included single marital status, receiving welfare support, age less than 20 years, and not having graduated from high school. The more of these factors present, the greater the increase in the rate of prematurity, say the scientists. They conclude that these risks, along with low hematocrit levels and related factors, account for all the increased risk of premature births to black women.

Researchers at the National Center for Health Statistics in Hyattsville, Md., and the Bureau of Health Care Delivery and Assistance in Rockville, Md., divided the category "low-birthweight' into the standard subgroups of very-low-birthweight (less than 1,500 grams) and moderately-low-birthweight (1,500 to 2,500 grams) for their analysis of 1983 birth certificate data from 47 states. Compared to white women, black women are three times more likely to have a very-low-birthweight infant and more than twice as likely to have one of moderately low birthweight. Using similar data, the authors also conclude that, between 1973 and 1983, "births of infants with moderately low birthweights decreased more among whites than among blacks, whereas births of infants with very low birthweights increased among blacks and decreased among whites.' They agree that socioeconomic factors play a role, but they say that the contribution to infant mortality by births to black teenagers has been "overemphasized' and that solutions "may be more complex than previously believed.'