On the federal level, the CDC has done its first study of maternal homicide using national data to examine the risk by age, race and start of prenatal care. While that study awaits publication, CDC officials said they had no national numbers on maternal homicide but did release a slide presentation, which reported 281 cases in 16 southern states and the District from 1991 to 1997.
The CDC has started a program to compile and analyze detailed characteristics about violent deaths across the country -- the National Violent Death Reporting System -- but it does not uniformly note maternal status in homicides.
In the latest wave of research, experts have used an expanded definition of what qualifies as deaths associated with pregnancy -- up to 12 months postpartum -- with the idea that some troubles surface after pregnancy ends. Postpartum depression, for example, may play a role in suicide cases. Likewise, homicides can be related to the "chain of events" started by a pregnancy.
In a CDC study of postpartum mothers, those younger than 20 were almost three times as likely to be homicide victims as their counterparts who were not recently pregnant.
Health experts say the better they understand maternal homicide, the better they can tailor efforts to prevent harm during that pivotal time. Most women see doctors repeatedly during pregnancy -- when, the thinking goes, there is a chance to help.
"It's a time when women are open, they are very receptive to information, and they are interested in protecting their children," said researcher Judith McFarlane of Texas Woman's University.
Some criminologists, such as Neil Websdale of Northern Arizona University, say there is a risk in overstating the problem. Websdale pointed out that more than 1,000 women a year are killed in domestic clashes, the overwhelming majority of whom are not pregnant. But Jack Levin of Northeastern University stressed the counterpoint. "This should not have to become an epidemic to get the public's attention," he said.
Determining the precise risk of homicide for new and expectant mothers is not easy, said researcher Isabelle Horon, because the number of pregnancies in a year is unclear. In Maryland, Horon and her co-author instead ranked leading causes of death. Homicide came in fifth for all Maryland women ages 14 to 44 who had not been recently pregnant. For those who were or had been recently pregnant, homicide was first.
After making statistical adjustments for age and race, the Maryland researchers found that pregnant women and new mothers were still almost twice as likely to die of homicide as their counterparts who had not recently been pregnant.
Staff researcher Bobbye Pratt contributed to this report.