Impact of endometrioma on iron levels and oxidative stress in the follicular fluid in women with endometriosis: a cross-sectional study

The cause of infertility in women with endometriosis remains unclear. Elevated levels of iron in the follicular fluid (FF), potentially leading to oxidative stress, have been reported in endometriosis. In this study, we aimed to compare markers of iron status, oxidative stress, and inflammation in the FF of infertile women with and without endometriosis. Infertile women undergoing assisted reproductive technology (ART) were the subjects of the study. Endometriosis (n = 21) was diagnosed laparoscopically, and the control arm (n = 14) comprised women with tubal factor, male factor, or unexplained infertility. FF collected during oocyte retrieval was used to estimate iron levels, transferrin, interleukin-6 (IL-6), and malondialdehyde (MDA). MDA levels were significantly higher in FF of women with endometriosis compared to controls. Interestingly, the MDA levels did not differ between affected and unaffected ovaries in women with unilateral endometrioma. In fact, MDA levels were significantly higher in the non-ovarian endometriosis compared to those with ovarian endometrioma. Iron, transferrin, and interleukin-6 (IL-6) were not significantly different between controls and those with endometriosis, and there were no correlations between MDA and iron or IL-6. In conclusion, our findings indicate that the presence of endometriomas does not worsen oxidative stress or elevate iron levels in the FF. These results suggest that the decision to surgically remove an endometrioma before ART should be taken based on clinical considerations such as accessibility issues during oocyte retrieval.