New York, May 2 (IANS): Regular use of low-dose "baby" aspirin, a common pain reliever, may reduce the risk of breast cancer in women, a new research has found.

For the study, published in the journal Breast Cancer Research, researchers analysed data from more than 57,000 women who were part of California's Teacher's Study.

The researchers saw an overall 16 per cent lower risk of breast cancer in women who reported using low-dose aspirin at least three times per week.

"The study found an interesting protective association between low-dose aspirin and breast cancer," said lead author Christina Clarke from the Cancer Prevention Institute of California.

"We did not by and large find associations with the other pain medications like ibuprofen and acetaminophen. We also did not find associations with regular aspirin since this type of medication is taken sporadically for headaches or other pain, and not daily for prevention of cardiovascular disease," Clarke said.

This study differed from other studies that have looked at aspirin and cancer risk because it focused on the dose levels of the aspirin women had taken and tracked the frequency of the use of low-dose aspirin as opposed to regular aspirin.

It was also able to look in detail at subtypes of breast cancer.

"We already knew that aspirin is a weak aromatase inhibitor and we treat women with breast cancer with stronger aromatase inhibitors since they reduce the amount of estrogen postmenopausal women have circulating in their blood," said Leslie Bernstein of the Department of Population Sciences, Beckman Research Institute of City of Hope in Monrovia, California.

"We thought that if aspirin can inhibit aromatase, it ought to reduce the likelihood that breast cancer would develop and it could also be an effective way to improve breast cancer patients' prognosis once they no longer take the more potent aromatase inhibitors," Bernstein said.

"Aspirin also reduces inflammation, which may be another mechanism by which aspirin taken regularly can lower risk of breast cancer developing or recurring," Bernstein added.

The researchers said they chose to focus on low-dose aspirin, because not only is it inexpensive and readily available, but because there are already a lot of people taking it for prevention of other diseases such as heart disease and even colon cancer.