Addition of zinc to human ejaculate prior to cryopreservation prevents freeze-thaw-induced DNA damage and preserves sperm function.

PURPOSE: To study the effect of addition of zinc to human semen sample prior to cryopreservation on post-thaw sperm quality and function. METHODS: Semen samples were collected from men attending university infertility clinic for semen analysis (n=109). Liquefied semen samples were cryopreserved in glycerol-egg yolk- citrate medium with or without the prior addition of zinc (100 µM) and stored in liquid nitrogen. After 10 days, the semen samples were thawed to assess the outcome. Sperm motility, DNA integrity, mitochondrial potential and the ability of spermatozoa to undergo capacitation and acrosome reaction was assessed in post-thaw samples. RESULTS: Semen samples cryopreserved after addition of zinc had a significantly higher percentage of sperm with intact DNA (p<0.001), mitochondrial function (p<0.001) and progressive motility (p<0.01) compared to the semen samples cryopreserved without zinc supplementation. Apart from this, ability to undergo capacitation and acrosome reaction in vitro was significantly higher in semen samples cryopreserved with zinc (p<0.0001 and p<0.001 respectively). CONCLUSIONS: Addition of zinc to semen samples prior to cryopreservation helps in preventing the freeze-thaw-induced sperm DNA damage and loss of sperm function.

Embryonic Aneuploidy after Preimplantation Genetic Screening: Age- and Indication-Matched Comparative Study between Indian and Spanish Population.

BACKGROUND: Recent studies show that there are differences in female fertility in different ethnic groups with ovarian aging and IVF treatment outcomes. Advanced maternal age is a known risk factor for miscarriage, accounting largely due to genetically abnormal fetus. AIMS AND OBJECTIVES: This study investigates if there are any differences in rates of embryo aneuploidy based on age and indications for preimplantation genetic screening (PGS) between Indian and Spanish women. MATERIALS AND METHODS: This multicenter study was carried out at fertility centers in India and Spain. Data from autologous IVF cycles of women <45 years age (Spanish: 39.4 ± 3.8 years; Indian: 35.3 ± 4.6 years) were included. A total of 37,962 embryos from 7009 IVF cycles from Spain and 1894 embryos from 308 IVF cycles from India, having similar clinical indications, underwent similar IVF treatment protocol. The embryos were analyzed by PGS using either a day-3 or day-5/6 embryo biopsy. RESULTS: Both Indian and Spanish ethnic population showed a reduction in aneuploidy rate in day-5/6 biopsy compared with day-3 biopsy (Spanish: 53.3% vs. 81.1%, P < 0.01; Indian: 50% vs. 75%, P < 0.02). There was a significant decrease in highly abnormal or chaotic embryos in trophectoderm biopsies compared with day-3 biopsies (Spanish: 2% vs. 16.1%, P < 0.01; Indian: 2.5% vs. 17.7%, P < 0.01). Both the populations showed similar trend in aneuploidy rate with maternal age. The results showed no significance between aneuploidy rate compared within different age groups and indications. However, there was a significant reduction in the miscarriage rate in Spanish population in day-3 biopsy compared with Indian population (10.7% vs. 19.8%; P < 0.05; 95% confidence interval [0.0044-0.0712]). There were no differences in the clinical outcomes compared between the two populations. CONCLUSION: This study shows that the aneuploidy rates between Indian and Spanish women of the same age group undergoing IVF treatment do not differ. An in-depth analysis to compare the types of anomalies reported with PGS in both the population will be of much interest.

Morphokinetic behavior of euploid and aneuploid embryos analyzed by time-lapse in embryoscope.

BACKGROUND: Embryonic aneuploidy may result in miscarriage, implantation failure, or birth defects. Thus, it is clinically necessary to avoid the selection of aneuploid embryos during in vitro fertilization treatment. AIM: The aim of this study was to identify the morphokinetic differences by analyzing the development of euploid and aneuploid embryos using a time-lapse technology. We also checked the accuracy of a previously described model for selection of euploid embryos based on morphokinetics in our study population. MATERIALS AND METHODS: It is a retrospective study of 29 cycles undergoing preimplantation genetic screening from October 2013 to April 2015 at our center. Of 253 embryos, 167 suitable for biopsy embryos were analyzed for their chromosomal status using array-comparative genome hybridization (CGH). The morphokinetic behavior of these embryos was further analyzed in embryoscope using time-lapse technology. RESULTS: Among the analyzed embryos, 41 had normal and 126 had abnormal chromosome content. No significant difference in morphokinetics was found between euploid and aneuploid embryos. The percentage of embryos with blastulation was similar in the euploid (65.85%, 27/41) and aneuploid (60.31%, 76/126) embryos (P = 0.76). Although hard to define, majority of the chromosomal defects might be due to meiotic errors. On applying embryo selection model from Basile et al., embryos falling within optimal ranges for time to division to 5 cells (t5), time period of the third cell cycle (CC3), and time from 2 cell division to 5 cell division (t5-t2) exhibited greater proportion of normal embryos than those falling outside the optimal ranges (28.6%, 25.9%, and 26.7% vs. 17.5%, 20.8%, and 14.3%). CONCLUSION: Keeping a track of time interval between two stages can help us recognize aneuploid embryos at an earlier stage and prevent their selection of transfer. However, it cannot be used as a substitute for array CGH to select euploid embryos for transfer.