FRIDAY, March 28 (HealthDay News) -- Giving birth early seems to increase a woman's risk of having high cholesterol later, a new study shows.

And that raises the chances of heart disease even further down the line for these women, the researchers added.

The findings were presented Thursday at the Society for Gynecologic Investigation annual meeting, in San Diego.

"Total cholesterol and LDL cholesterol were elevated in women who'd had a preterm birth, before 34 weeks," said study author Janet Catov, an assistant professor of obstetrics, gynecology and reproductive sciences at the University of Pittsburgh School of Medicine.

Catov said it's hard to know yet whether there's something in the pregnancy or preterm delivery that triggers the high cholesterol, or if it's the high cholesterol that may have something to do with the preterm delivery. She did note that "very early in pregnancy, women with preterm birth have elevated lipids, which may be exacerbated in pregnancy."

Another recent study found that women with very low levels of cholesterol were also at risk of preterm birth, but Catov said this study showed that women on the very high end of cholesterol levels also went on to give birth prematurely.

"Perhaps there's a normal range, and if you're higher or lower, it could be a problem," she said.

In the current study, Catov and her colleagues compared 47 women who'd had a preterm birth, defined as giving birth before 37 weeks of gestation, to 104 women who gave birth to full-term infants. Most of the women in the preterm group gave birth before 34 weeks of gestation.

Women who had other chronic medical conditions, such as preeclampsia or a baby with signs of growth restriction, were excluded from the study.

Blood samples were taken an average of 7.4 years after delivery.

Women who'd given birth before 34 weeks of gestation had the highest levels of total cholesterol at 202.6 mg/dl. Women who gave birth between 34 and 37 weeks had levels of 190.1 mg/dl, and women who carried their babies to term had levels of 180.1 mg/dl.

After adjusting for race, smoking history and body mass index, the researchers found that women who gave birth prematurely had a 2.3 times greater risk of developing cholesterol levels above 240 mg/dl, a level considered high risk by the American Heart Association.

Additionally, women who'd had a preterm birth were 3.3 times more likely to have elevated LDL -- the "bad" cholesterol -- than women who gave birth to full-term babies.

"What this study tells us is that a woman's previous medical history, particularly conditions that happen during pregnancy, may be a clue to her later heart disease risk," said Dr. Nieca Goldberg, director of the New York University Medical Center's Women's Heart Program.

"I would advise a woman who's had a preterm birth and who now has high cholesterol to have her cardiac risk factors evaluated at regular intervals, at least with a yearly physical," said Goldberg.

While Catov said these findings need to be duplicated in a larger study before any specific guidelines or recommendations can be made, she said it's a good idea to "keep your doctor apprised of your medical conditions and preterm births or other adverse pregnancy outcomes, and keep up to date with recommended screenings."

More information

To learn more about cholesterol and how to lower your levels, visit the American Heart Association  .

TUESDAY, March 25 (HealthDay News) -- The use of a less invasive form of sentinel lymph node biopsy (SLNB) during breast cancer surgery increased substantially in the United States from 1998 to 2005, researchers say. However, there are still disparities in terms of which women receive the therapy.

The study by the American Cancer Society found that non-white women, women aged 72 and older, and women living in poor areas of the country were less likely to receive the SLNB staging test than those who were white, younger, or live in more affluent areas.

In women diagnosed with breast cancer, doctors check to see if the cancer has spread from the breast tissue into neighboring lymph nodes. This can be done by removing many lymph nodes in a procedure called axillary lymph node dissection (ALND) or by removing a few lymph nodes (SLNB), which is associated with easier recovery and fewer long-term problems, according to background information in the study.

In this study, researchers analyzed national data on women who had breast cancer surgery between 1998 and 2005. Clinical care guidelines were changed in 1998 to allow surgeons to use SLNB in certain patients.

The proportion of patients who had SLNB increased from 26.8 percent in 1998 to 65.5 percent in 2005, the study found.

But the researchers also found that disparities in the use of SLNB persisted during those years. For example, in 1998, 29 percent of white women received SLNB, compared with 26 percent of black women, and 35 percent of Hispanic women. By 2005, the rates were 70 percent, 64 percent, and 67 percent, respectively.

According to clinical guidelines, SNLB should only be done in centers that have experienced teams. This study didn't examine whether the disparities in access to SLNB may be related to lack of experience at certain facilities.

"The disparities that were related to receipt of SLNB in this study are particularly important in light of the clinical advantages associated with this technique. Better outcomes have been reported for patients receiving SLNB than for patients receiving ALND," the researchers wrote.

The study was published online March 25 in the Journal of the National Cancer Institute.

"Given America's track record of disparate care, I suppose we should not be surprised that racial and ethnic minorities were disproportionately deprived of another medial advance," Dr. Stephen B. Edge, of Roswell Park Cancer Institute in Buffalo, wrote in an accompanying editorial. "However, this observation is profoundly disappointing and sobering. It is yet another call for us to redouble efforts to identify and correct the root cause of disparities."

More information

The U.S. National Cancer Institute has more about SLNB.

FRIDAY, March 21 (HealthDay News) -- Women suffer more damage to their cardiovascular health from poor sleep than men do, and researchers at Duke University Medical Center believe they've determined why.

They found that poor sleep is associated with greater psychological distress and higher levels of biomarkers associated with increased risk of type 2 diabetes and heart disease. They also found that these associations are stronger in women than in men.

"This is the first empirical evidence that supports what we have observed about the role of gender and its effects upon sleep and health," study author Edward Suarez, an associate professor in the department of psychiatry and behavioral sciences, said in a prepared statement.

"The study suggests that poor sleep -- measured by the total amount of sleep, the degree of awakening during the night, and most importantly, how long it takes to get to sleep -- may have more serious health consequences for women than for men," he said.

The study was published online in the journal Brain, Behavior and Immunity.

Even though women are twice as likely as men to report sleep problems, most sleep studies in the past have focused on men, said Suarez, who added that this pattern has been slowly changing in recent years.

This new study included 210 healthy middle-aged women and men without any history of diagnosed sleep disorders. None of them smoked or took any medications on a daily basis. The participants filled out a standard sleep quality questionnaire and were assessed for levels of depression, anger, hostility and perceived social support. Blood samples from the participants were analyzed for levels of biomarkers associated with increased risk of diabetes and heart disease.

About 40 percent of the participants were classified as poor sleepers, meaning they had frequent problems falling asleep or awoke frequently during the night. While the men and women in the study had similar sleep quality ratings, their risk profiles were dramatically different, the researchers said.

"We found that for women, poor sleep is strongly associated with high levels of psychological distress, and greater feelings of hostility, depression and anger. In contrast, these feelings were not associated with the same degree of sleep disruption in men," Suarez said.

Women who were poor sleepers also had higher levels of C-reactive protein and interleukin-6 -- inflammation biomarkers associated with increased risk of heart disease and higher levels of insulin.

"Interestingly, it appears that it's not so much the overall poor sleep quality that was associated with greater risk, but rather the length of time it takes a person to fall asleep that takes the highest toll. Women who reported taking a half hour or more to fall asleep showed the worst risk profile," Suarez said.

He suggested the sleep/health risk differences between men and women may be partly due to variations in the activity of the number of naturally occurring substances in the body, such as the amino acid tryptophan, the neurotransmitter serotonin, and the neurohormone melatonin.

"All of these substances are known to affect mood, sleep, onset of sleep, inflammation and insulin resistance," said Suarez, who plans further research into the link between poor sleep and health risk in women and men.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about sleep.

FRIDAY, March 14 (HealthDay News) -- Higher anxiety levels may help elderly women live longer, but may harm older men, U.S. research shows.

A team at the Cleveland Clinic and Case Western Reserve University followed 1,000 seniors in three Florida retirement communities for up to 15 years.

They found that women with higher levels of anxiety at the start of the study lived longer than others. Year-to-year changes in anxiety levels didn't appear to affect women's survival, either.

In contrast to women, men with higher anxiety levels at the start of the study were more likely to die earlier, the researchers said.

"Our research indicates that anxiety may have a protective effect on women, possibly causing them to seek medical attention more frequently than men," Dr. Jianping Zhang, of the department of psychiatry and psychology at the Cleveland Clinic, said in a prepared statement. "In contrast, increasing anxiety over time is more detrimental to men. Additional research is needed to better understand the mechanisms and effects of anxiety in men and women."

The study is noteworthy due to the large amount of data collected over a long period of time, noted co-researcher Dr. Leo Pozuelo, who is also in the department of psychiatry and psychology at the Cleveland Clinic.

"Baseline higher anxiety could have led the female study participants to be more active and health-conscious," Pozuelo said in a prepared statement. "We are not certain of the absolute connection between anxiety and mortality, but this data set shows there may be a gender difference."

The study was to be presented Thursday at the annual meeting of the American Psychosomatic Society.

More information

The American Academy of Family Physicians has more about anxiety  .