Heart disease is the top cause of pregnancy-related deaths in California, but almost one-third of those deaths could be prevented, a new study suggests.
 

"Women who give birth are usually young and in good health. So heart disease shouldn't be the leading cause of pregnancy-related deaths, but it is," lead researcher Dr. Afshan Hameed, an associate professor of clinical cardiology, obstetrics and gynecology at the University of California, Irvine, said in an American Heart Association (AHA) news release.
 

From 2002 to 2005, there were 2.1 million live births in California. Hameed and her colleagues analyzed the medical records of 732 women in the state who died from all causes while pregnant or within one year of pregnancy, and found that 209 of those deaths were pregnancy-related.
 

About one-quarter (52) of the pregnancy-related deaths were from some form of heart disease. Only 6 percent of these women who died had been diagnosed with a heart condition before the pregnancy.
 

Two-thirds (33) of the heart-related deaths were from cardiomyopathy, a disease in which the heart muscle is weakened and that can lead to heart failure, irregular heartbeats, heart valve problems and death.
 

Women most likely to die from pregnancy-related heart disease were black, obese or were substance abusers during pregnancy. Nearly one-fourth of the pregnant women who died of heart disease had been diagnosed with high blood pressure during their pregnancies.
 

In about two-thirds of the deaths, the diagnosis was either incorrect or delayed or doctors gave ineffective or inappropriate treatments, according to the researchers. One-third of the patients who died had failed to seek or had delayed care, 10 percent refused medical advice and 27 percent did not recognize their symptoms as heart-related.
 

The findings, which were scheduled for presentation Nov. 17 at the AHA's annual meeting in Dallas, likely apply to the rest of the United States, according to Hameed.
 

"Women should attain and maintain proper weight before and during pregnancy, and talk to their doctors if they have personal or family histories of heart disease," she said.
 

"And health care providers should be referring pregnant women who complain of symptoms consistent with cardiac disease to specialists, especially when these risk factors are present. Women with evidence of substance abuse should receive early referral for treatment," Hameed added.
 

However, it is impossible to be certain whether earlier diagnosis and intervention would have prevented death in these cases "as missed cues to the presence of heart disease were common," she said.
 

Because the study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
 

Maternal death rates have been rising in California and the United States since the mid-1990s, according to the California Department of Public Health.