An increasing waistline ups the risk of breast cancer post-menopause by 33 percent, a new study suggests.

As such menopause does not increase the risk of breast cancer. According to WebMD, age is a risk factor for breast cancer and its chances of developing increase with age. Nearly 95 percent of women diagnosed with breast cancer each year are over age 40, and about half are age 61 and older.

For the current study, the researchers examined nearly 93,000 women aged above 50 who experienced menopause. All of them partook in the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) and were not diagnosed with breast cancer at the time of the study between 2005 and 2010 and had BMI of 25-26. The participants were highly educated with university degrees.

Researchers monitored the participants for three to four years and they asked them about continuing use of HRT; their general health; a subsequent diagnosis of cancer; and lifestyle, including how much they smoked and drank.

The findings revealed that 1090 women developed breast cancer, giving an absolute risk of just over 1 percent. Researchers noted that infertility treatment, family history of breast/ovarian cancer and use of HRT were all commonly related with an increased risk of being diagnosed with the disease, while pregnancies were protective.

According to the researchers, increase in the skirt size of women every 10 years was associated with a 33 percent higher risk of developing breast cancer after menopause; going up two skirt sizes in the same period increased the risk by 77 percent.

Expanding waist line has been linked to other cancers, including those of the pancreas, lining of the womb, and ovaries, the researchers point out, possibly because midriff fat is more harmful.