Endometrial HOXA10 mRNA Expression in PCOS Patients at High Risk for Ovarian Hyperstimulation Syndrome

Background: This study was designed to determine whether the risk of ovarian hyperstimulation syndrome (OHSS) contributes to the subfertility in PCOS. Endometrial HOXA-10 mRNA expression, a well-characterized gene essential to endometrial receptivity, was evaluated in PCOS patients whose embryos are planned to be frozen due to the risk of OHSSS. Methods: Twent-five women with PCOS in high risk group for OHSS and age and BMI matched 25 non-PCOS infertile patients were included the study. Five fertile women were accepted as positive control. Following egg collection each group of subject underwent total embryo freezing. After the egg collection, endometrial sampling was performed with a pipella cannula from each gruop of participant and fertile control. Expression levels of HOXA-10 mRNA were determined by RT-PCR. Gene expression results are presented as Ct (cycle threshold), ΔCt, and ΔΔCt. Reults: Average ΔCt value of HOXA-10 mRNA in PCOS, non-PCOS and fertile groups were found to 5.88, 6.77, and 7.79 respectively. Compared to endometrial HOXA-10 mRNA levels of fertile cases, the HOXA-10 mRNA levels of the patients in the PCOS group were found to be significantly lower (ΔCt 7.79 vs. ΔCt 5.88, p<0.002). Similarly, endometrial HOXA-10 mRNA levels in the non-PCOS control group were significantly lower than the HOXA-10 mRNA levels in the fertile group (ΔCt 6.77 vs. ΔCt 7.79, p<0.001). HOXA-10 mRNA levels in endometrial samples taken from patients in the PCOS group were found to be significantly lower than the HOXA-10 mRNA levels in non-PCOS control group. Conclusions: HOXA-10 mRNA levels were found to be lower in PCOS patients with high risk for OHSS compared to both fertile and infertile patients without PCOS. OHSS risk in PCOS decreases endometrial HOXA-10 mRNA expression.