Immunoreactive endothelin-1 concentrations in follicular fluid of women with and without endometriosis undergoing in vitro fertilization-embryo transfer

Objective: To determine the concentrations of immunoreactive (IR) endothelin-1 in human follicular fluid (FF) and whether IR-endothelin-1 levels are different in women with endometriosis-associated infertility. Design: Follicular fluid and plasma samples, obtained from women with and without endometriosis undergoing IVF-ET, were collected at the time of oocyte aspiration and analyzed for IR-endothelin-1 levels. Setting: Infertility clinic in an academic research environment. Results: Overall, 90% of FF samples and 60% of plasma samples contained IR-endothelin-1 detectable above the threshold of assay sensitivity. Immunoreactive endothelin-1 levels (mean ± SEM) in FF samples from women with and without endometriosis-associated infertility were 74 ± 12 and 37 ± 6 pg/mL, respectively. There was no difference in IR-endothelin-1 levels in FF samples between controlled ovarian hyperstimulation cycles with or without leuprolide acetate. No significant differences were detected in plasma IR-endothelin-1 levels in women with endometriosis-associated infertility when compared with those without. Conclusions: These results demonstrate the presence of IR-endothelin-1 in human FF obtained at the time of oocyte aspiration for IVF-ET and higher levels of IR-endothelin-1 in FF of women with endometriosis-associated infertility.