By Jimmy Downs

Wednesday Jan 9, 2013 (foodconsumer.org) -- Breastfeeding babies for a longer period may reduce risk of developing ovarian cancer, a study in American Journal of Clinical Nutrition suggests.

D. Su from School of Public Health, Curtin University in Perth, Australia and colleagues conducted the study and found women breastfeeding their babies for more than 31 months had their risk of ovarian cancer reduced by 91%, compared with those who had their lactation for less than 10 months.

The researchers also found women who breastfed three or more children had their risk of ovarian cancer reduced by 62%, compared with women breastfeeding only one child.

The case-control study involved 493 incident ovarian cancer patients and 472 hospital-based controls, both groups at a mean age of 59 years, who were residents in Guangzhou, Guangdong province, China.

The researcher concluded " Prolonged lactation is associated with a lower risk of ovarian cancer in parous Chinese women."

Ovarian cancer is hard to diagnose and treat, according to the researchers and therefore any effective prevention was highly desired.  The researchers conducted the study in hopes that they could find some ways to help women to reduce their risk for ovarian cancer.

Breastfeeding has already been associated with reduced risk of breast cancer in other studies.  Both breast cancer and ovarian cancer have something to do with female reproductive or sex hormone.  Longer lactation or breastfeeding allows women to have less exposure to high levels of hormones, which may explain why there is an inverse association between the lactation period and risk of ovarian cancer.

Ovarian cancer was expected to be diagnosed in more than 22,280 women in 2012 in the United States and the disease and complications were expected to kill 15,500 in 2012, according to the National Cancer Institute.

Ovarian cancer symptoms include abnormal vaginal bleeding or discharge, pelvic or abdominal pain, back pain, bloating, feeling full quickly while eating, and changed bathroom habits such as passing urine very badly or very often, constipation or diarrhea.