Women with diabetes are at a greater risk of developing breast cancer, especially post menopause, a new study says.

Researchers say that the risk is almost 30 percent higher for women who have diabetes type-2.

An estimated 226,870 women will develop breast cancer in the year 2012, according to the National Cancer institute. Risk factors for breast cancer include, gender, age and menstrual cycle along with certain genetic mutations. Women who've had early start of periods (before age 12) or late menopause (after age 55) have an increased risk of developing breast cancer.

"Our study found a significantly increased risk of breast cancer in women who had diabetes which was restricted to women after the age of menopause," said Professor Peter Boyle, lead author of the study.

Researchers arrived at this result after analyzing 40 studies done on diabetes acting as a risk factor for breast cancer.

The studies, examined by the International Prevention Research Institute, had analyzed 56,000 breast cancer cases across four continents. Researchers found that post-menopausal women have an additional risk of developing breast cancer if they have diabetes type-2.

Researchers found no such association between breast cancer and diabetes for pre-menopausal women or women who had diabetes type 1.

They say that high body mass index, seen in people who develop diabetes type 2, may explain the risk factor.

"We don't yet know the mechanisms behind why type II diabetes increases the risk of breast cancer. On the one hand, it's thought that being overweight, often associated with type II diabetes, and the effect this has on hormone activity may be partly responsible for the processes that lead to cancer growth. It is also impossible to rule out that some factor(s) related to diabetes may be involved in the process," said Boyle who is also the president of IPRI.

The latest research adds to the long list of complications associated with diabetes that affects various body functions like kidneys, nerves, feet and eyes. Being a diabetic increases a person's risk of developing heart disease. Other complications like certain skin problems, sexual dysfunction, digestive problems, problems with teeth and gums are also associated with diabetes.