A study finds there may one plus to having migraine headaches: a reduced risk of breast cancer.

Researchers in Seattle studied more than 9,000 people and found that those with a history of migraines were 26 percent less likely to develop breast cancer. Low estrogen levels appear to increase the severity and frequency of migraines in women while decreased levels of the hormone are known to boost breast cancer risk.

Scientists say more research is needed but they believe migraine patients’ greater use of non-steroidal anti-inflammatory drugs could explain some of their lower breast cancer risk as these drugs have been linked to a 12 percent lower breast cancer risk in previous studies.