Tunel assay on swim up samples AIDS in predicting IVF outcomes

Abstract

To evaluate the results of TUNEL testing on unprocessed and processed sperm samples used for fertilization during an IVF cycle and outcome. Prospective study. TUNEL assay was performed on the unprocessed semen sample (A), the swim-up or density gradient sample used to fertilize the oocytes (B), and on the fraction of sperm usually discarded after processing (C) in a series of unselected patients undergoing ART at our center. Semen parameters, male and female age, female FSH and AMH, number of eggs retrieved, fertilization rate, and use of ICSI were recorded and analyzed. Interactive clustering analysis was used to determine TUNEL thresholds for each sample group. Pregnancy was used as the primary outcome measure. Data on 47 couples were analyzed. Mean age (95%CI) of males was 35.3 (34.3-36.3), and females was 34.2 (33.3 to 35.1). Mean sperm density was 76 mil/ml (63-89), motility 49% (45-52), Kruger morphology 7.9% (1.5-14.3). Processing the sperm statistically decreased the percentage of TUNEL positive sperm from 9.48 (95% CI)to 2.12 (95% CI) P<0.0001. TUNEL results of (A) correlated with (C) (r=0.52, P=0.0003). TUNEL results of (C) was the best predictor of positive pregnancy but especially in 19 nulligravid women The relative risk of failure to achieve a pregnancy was 1.8 (1.0-3.2) for TUNEL >10% (P=0.02), and 2.5 (0.9-6.7) for TUNEL>15% (P=0.05). No pregnancies were observed in 4 patients if TUNEL was >25% (P=0.002). For couples with TUNEL <5 %, 80% of couples achieved pregnancy in the evaluated treatment cycle vs 53% with TUNEL > 5%. TUNEL testing may aid in predicting outcomes of IVF. Since the threshold of DNA fragmentation in sperm needs to be fairly high before the sperm will be TUNEL positive, the results of the unused sample after processing may provide the most insight into IVF outcomes.