New York: What has previously been known as good cholesterol - high density lipoprotein (HDL) - may actually contribute to heart diseases in women while they are transitioning through menopause, new research has found.

The researchers found that HDL, the "good cholesterol", may not protect women against atherosclerosis, better known as hardening of the arteries that typically occurs as the result of high blood pressure, smoking and/or cholesterol.

The findings suggest that women more vulnerable to artery hardening during menopause.

While HDL has well-documented benefits in protecting against the hardening process, which can lead to heart attacks and strokes, the new study showed that these benefits are diminished during the menopause transition probably due to hormonal alterations. 

The study included 225 women in their mid and late 40s who had up to five measures of plaque buildup over a maximum of nine years of follow-up. 

All participants were tested and diagnosed as being free of any cardiovascular disease at the time of the baseline scan.

"What we found is that, as women transition through menopause, increases in good cholesterol were actually associated with greater plaque buildup," said lead author for the study Samar El Khoudary, assistant professor at University of Pittsburgh Graduate School of Public Health in the US.

"These findings suggest that the quality of HDL may be altered over the menopausal transition, thus rendering it ineffective in delivering the expected cardiac benefits," Khoudary noted.

The findings were presented at the annual meeting of The North American Menopause Society (NAMS) in Las Vegas, US.