A study published in March 2008 has determined that women with endometriosis who took high dose anti-oxidants did not show any improvement in their pregnancy rates. Oxidative stress is a condition which occurs when the production of free radicals in the human body exceeds the body's ability to neutralize and eliminate them. Oxidative stress can result from a lack of antioxidants or from an over abundance free radicals. Excess free radicals can result in cellular damage. Some scientists believe that this may interfere with pregnancy. Past studies have identified an association in women with endometriosis and higher levels of free radicals or oxidative stress. Some authors believe that oxidative stress may be partially responsible for the development of endometriosis.

Endometriosis study

Thirty four women with endometriosis were divided into two groups. One group received a bar containing high doses of vitamin C and vitamin E. The other group received a bar that did not contain the vitamins. Each group took the bars for six months. At the end of six months, the investigators sampled fluid from the abdomen and obtained blood samples to measure levels of two free radicals. The compounds studied, malondialdehyde (MDA) and lipid hydroperoxides (LOOHs),  are considered to be measures of oxidative stress. 

After 4 months, the women who took vtiamin c and vitamin E had lower levels of MDA and LOOHs than the women who did not.  However, The pregnancy rates were no different between the two groups. Conclusions Vitamins C and E supplementation was associated with a decrease in the concentration of oxidative stress markers in women with endometriosis. Pregnancy rates did not improve, however. Based on the current data, there is no basis for recommending this treatment to women with endometriosis.