Clues to a perilous pregnancy.

The development of high blood pressure during pregnancy often serves as the first of preeclampsia and eclampsia. These related conditions constitute the third leading cause of pregnancy-related deaths in the United States, federal researchers determined last year. The same scientists are now homing in on factors -- such as inadequate prenatal care -- that may help identify women at mortal risk from these killers.

Women who suffer from preeclampsia, the milder condition, generally develop high blood pressure and a swelling of the hands and feet. Those who go on to develop eclampsia can also suffer seizures -- and sometimes coma.

After analyzing maternal-mortality data from a large survey of U.S hospitals between 1979 and 1986, Herschel W. Lawson and his colleagues at the Centers for Disease Control in Atlanta discovered that minority women face twice the risk of death from complications of preeclampsia compared with white women with preeclampsia, and run a 60 percent greater risk of death from eclampsia that do white women with this condition.

When the researchers adjusted for age and race, their data revealed that unmarried women with preeclampsia die at twice the rate of their married counterparts. Lawson says his team was also surprised to find that many of the women died of preeclampsia or eclampsia had not received adequate prenatal care. This suggests that some of these deaths might have been prevented, he says.