Björndahl, L. and Kvist, U. Sequence of ejaculation affects the spermatozoon as a carrier and its message. Reprod Biomed Online 2003; 7:440–8.CrossRefGoogle ScholarPubMed

Overstreet, J. W. et al. In-vitro capacitation of human spermatozoa after passage through a column of cervical mucus. Fertil Steril 1980; 34:604–6.CrossRefGoogle ScholarPubMed

Björndahl, L., Mohammadieh, M., Pourian, M., Söderlund, I. and Kvist, U. Contamination by seminal plasma factors during sperm selection. J Androl 2005; 26:170–3.CrossRefGoogle ScholarPubMed

World Health Organisation (WHO). laboratory Manual for the Examination and Processing of Human Semen (5th edn.) (Cambridge University Press, 2010).Google Scholar

Mortimer, D. Laboratory standards in routine clinical andrology. Reprod Med Rev 1994; 3:97–111.CrossRefGoogle Scholar

Mortimer, D. Practical Laboratory Andrology (Oxford University Press, 1994).CrossRefGoogle Scholar

Aitken, R. J. and Clarkson, J. S. Significance of reactive oxygen species and antioxidants in defining the efficacy of sperm preparation techniques. J Androl 1988; 9:367–76.Google Scholar

Ramasamy, R., Yagan, N. and Schlegel, P. N. Structural and functional changes to the testis after conventional versus microdissection testicular sperm extraction. Urology 2005; 65:1190–4.CrossRefGoogle Scholar

Palermo, G., Joris, H., Devroey, P. and van Steirteghem, A. C. Pregnancies after intracytoplasmic sperm injection of single spermatozoan into an oocyte. Lancet 1992; 340:17–8.CrossRefGoogle Scholar

Craft, I., Twirigotis, M., Bennett, V., Taranissi, M., Khalifa, Y. et al. Percutaneous epididymal sperm aspiration and intracytoplasmic sperm injection in the management of infertility due to obstructive azoospermia. Fertil Steril 1995; 63:1038–42.Google Scholar

Devroey, P., Liu, J., Nagy, Z. P., Goossens, A., Tournaye, H. et al. Pregnancies after testicular extraction (TESE) and intracytoplasmic sperm injection (ICSI) in non-obstructive azoospermia. Hum Reprod 1995; 10:1457–60.Google Scholar

Bachtell, N. E., Conaghan, J. and Turek, P. J. The relative viability of human spermatozoa from the vas deferens, epidydmis and testis before and after cryopreservation. Hum Reprod 1999; 14(12):3048–51.CrossRefGoogle ScholarPubMed

Nagy, Z. P., Joris, H., Verheyen, G., Devroey, P. and Van Steirteghem., A. C. Correlation between motility of testicular spermatozoa, testicular histology and the outcomes of intracytoplasmic sperm injection. Hum Reprod 1998; 13:890–5.CrossRefGoogle ScholarPubMed

Park, Y.-S., Lee, S.-H., Sang, J. S., Jun, J. H., Koong, M. K. et al. Influence of motility on the outcome of in vitro fertilization/intracytoplasmic sperm injection with fresh vs. frozen testicular sperm from men with obstructive azoospermia. Fertil Steril 2003; 80:526–30.CrossRefGoogle ScholarPubMed

Ohlander, S., Hotaling, J., Kirshenbaum, E., Niederberger, C. and Eisenberg, M. L. Impact of fresh versus cryopreserved testicular sperm upon intracytoplasmic sperm injection pregnancy outcomes in men with azoospermia due to spermatogenic dysfunction: a meta-analysis. Fertil Steril 2014; 101:344–9.CrossRefGoogle ScholarPubMed

Karacan, M., Alwaeely, F., Erkan, S., Cebi., Z., Berberoglugi, M. et al. Outcome of intracytoplasmic sperm injection cycles with fresh testicular spermatozoa obtained on the day of or the day before oocyte collection and with cryopreserved testicular sperm in patients with azoospermia. Fertil Steril 2013; 100:975–80.Google Scholar

Ord, T., Marello, E., Patrizio, P., Balmaceda, J. P., Silber, S. J. et al. The role of the laboratory in the handling of epididymal sperm for assisted reproductive technologies. Fertil Steril 1992; 57:1103–6.CrossRefGoogle ScholarPubMed

Craft, I. and Tsirigotis, M. Simplified recovery, preparation and cryopreservation of testicular spermatozoa. Hum Reprod 1995; 10:1923–7.CrossRefGoogle ScholarPubMed

Ramasamy, R., Reifsnyder, J. E., Bryson, C., Zaninovic., N., Liotta, D. et al. Role of tissue digestion and extensive sperm search after microdissection testicular sperm extraction. Fertil Steril 2011; 96(2):299–302.CrossRefGoogle ScholarPubMed

Nagy, Z. P., Verheyen, G., Tournaye, H., Devroey, P. and Van Steirteghem, A. C. An improved treatment procedure for testicular biopsy specimens offers more efficient sperm recovery: case series. Fertil Steril 1997; 376–9.CrossRefGoogle Scholar

Esteves, S. C. and Verza, S. Jr. PESA/TESA/TESE sperm processing. In Practical Manual of In Vitro Fertilization: Advanced Methods and Novel Devices, ed. Nagy, Z. P., Varghese, and Agarwal, A. (pp. 207–20) (Berlin: Springer Science + Business Media, 2012).Google Scholar

Popal, W. and Nagy, Z. P. Laboratory processing and intracytoplasmic sperm injection using epididymal and testicular spermatozoa: what can be done to improve outcomes? Clinics 2013; 68(S1):125–30.CrossRefGoogle ScholarPubMed

Muller, C. H. and Pagel, E. R. Recovery, isolation, identification, and preparation of spermatozoa from human testis. In Spermatogenesis: Methods and Protocols (Methods in Molecular Biology 927), ed. Carrell, D. T. and Ashton, K. I. (pp. 227–40) (Berlin: Springer Science + Business Media, 2013).Google Scholar

Polge, C., Smith, A. U. and Parkes, A. S. Revival of spermatazoa after vitrification and dehydation at low temperatures. Nature 1949; 164:666.CrossRefGoogle Scholar

Bunge, R. G. and Sherman, J. K. Fertilizing capacity of frozen human spermatozoa. Nature 1953; 172:767–8.CrossRefGoogle ScholarPubMed

Di Santo, M., Tarozzi, N., Nadalini, M. and Borini, A. Human sperm cryopreservation: update on techniques, effect on DNA integrity, and implications for ART. Adv Urol 2012; 2012:854837.CrossRefGoogle Scholar

Isachenko, V., Isachenko, E., Katkov, I. I., Montag, M., Dessole, S. et al. Cryoprotectant-free cryopreservation of human spermatozoa by vitrification and freezing in vapor: effect on motility, DNA integrity, and fertilization ability. Biol Reprod 2004; 71:1167–73.Google Scholar

Isachenko, V., Maettner, R., Petrunkina, A. M., Sterzik, K., Mallmann, P. et al. Vitrification of human ICSI/IVF spermatozoa without cryoprotectants: new capillary technology. J Androl 2012; 33:462–8.CrossRefGoogle ScholarPubMed

Slabbert, M., du Plessis, S. S. and Huyser, C. Large volume cryoprotectant-free vitrification: an alternative to conventional cryopreservation for human spermatozoa. Andrologia 2015; 47:594–9.CrossRefGoogle ScholarPubMed

World Health Organization (WHO). laboratory Manual for the Examination and Processing of Human Semen (5th edn.) Geneva: World Health Organization, 2010.Google Scholar

AbdelHafez, F., Bedaiwy, M., El-Nashar, S. A., Sabanegh, E. and Desai, N. Techniques for cryopreservation of individual or small numbers of human spermatozoa: a systematic review. Hum Reprod Update 2009; 15:153–64.Google ScholarPubMed

Gangrade, B. K. Cryopreservation of testicular and epididymal sperm: techniques and clinical outcomes of assisted conception. Clinics 2013; 68(Suppl 1):131–40.CrossRefGoogle ScholarPubMed

Cohen, J., Garrisi, G. J., Congedo-Ferrara, T. A., Kieck, K. A., Schimmel, T. W. et al. Cryopreservation of single human spermatozoa. Hum Reprod 1997; 12:994–1001.CrossRefGoogle ScholarPubMed

Desai., N. N., Blackmon, H. and Goldfarb, J. Single sperm cryopreservation on cryoloops: an alternative to hamster zona for freezing individual spermatozoa. Reprod Biomed Online 2004; 9:47–53.CrossRefGoogle ScholarPubMed

Desai, N., Goldberg, J., Austin, C., Sabanegh, E. and Falcone, T. Cryopreservation of individually selected sperm: methodology and case report of a clinical pregnancy. J Assist Reprod & Genetics 2012; 29:375–9.Google Scholar

Coetzee, K., Ozgur, K., Berkkanoglu, M., Bulut, H. and Isikli, A. Reliable single sperm cryopreservation in Cell Sleepers for azoospermia management. Andrologia 2015.CrossRefGoogle Scholar

Pickering, S. J., Braude, P. R., Johnson, M. H., Cant, A. and Currie, J. Transient cooling to room temperature can cause irreversible disruption of the meiotic spindle in the human oocyte. Fertil Steril 1990; 54:102–8.CrossRefGoogle ScholarPubMed

Swain, J. E. Optimizing the culture environment in the IVF laboratory: impact of pH and buffer capacity on gamete and embryo quality. Reprod Biomed Online 2010; 21:6–16.CrossRefGoogle ScholarPubMed

Magli, M. C., Van den Abbeel, E., Lundin, K., Royere, D., Van der Elst, . J et al. Committee of the Special Interest Group on Embryology. Revised guidelines for good practice in IVF laboratories. Hum Reprod. 2008; 23(6):1253–62. Epub 28 March 2008. doi: 10.1093/humrep/den068Google Scholar

Practice Committee of American Society for Reproductive Medicine, Practice Committee of Society for Assisted Reproductive Technology. Revised guidelines for human embryology and andrology laboratories. Fertil Steril 2008; 90(5 Suppl.):S45–59. doi: 10.1016/j.fertnstert.2008.08.099.Google Scholar

Eppig, J. J., O’Brien, M. and Wigglesworth, K. Mammalian oocyte growth and development in vitro. Mol Reprod Dev 1996; 44:260–73.Google Scholar

Mehlmann, L. M. Stops and starts in mammalian oocytes: recent advances in understanding the regulation of meiotic arrest and oocyte maturation.Reproduction 2005; 130(6):791–9.Google Scholar

Rattanachaiyanont, M., Leader, A. and Léveillé, M. C. Lack of correlation between oocyte-corona-cumulus complex morphology and nuclear maturity of oocytes collected in stimulated cycles for intracytoplasmic sperm injection. Fertil Steril 1999; 71(5):937–40.CrossRefGoogle ScholarPubMed

Veeck, L. L.Oocyte assessment and biological performance. Ann NY Acad Sci 1988; 541:259–74.CrossRefGoogle ScholarPubMed

Veeck, L. L. The morphologic estimation of mature oocytes and their preparation for insemination. In In Vitro Fertilization, ed. Norfolk (p. 81). (Baltimore:Williams & Wilkins, 1986).Google Scholar

Pehlivan, T. Clasificación del complejo corona-cúmulo-ovocito. In Manual práctico de esterilidad y reproducción Humana-Laboratorio de reproducción asistida, ed. Remohi, Cobo, Prados, Romero, Pellicer (4th edn., pp. 115–20) 2012.Google Scholar

Trounson, A., Anderiesz, C. and Jones, G. Maturation of human oocytes in vitro and their developmental competence. Reproduction 2001; 121(1):51–75.CrossRefGoogle ScholarPubMed

Cha, K. T., Koo, J. J., Ko, J. J., Choi, D. H., et al. Pregnancy after in vitro fertilization of human follicular oocytes collected from nonstimulated cycles, their culture in vitro and their transfer in a donor oocyte program. Fertil Steril 1991; 55:109–13.Google Scholar

Trounson, A., Wood, C. and Kausche, A. In vitro maturation and the fertilization and developmental competence of oocytes recovered from untreated polycystic ovarian patients. Fertil Steril 1994; 62(2):353–62.Google Scholar

Barnes, F. L., Crombie, A., Gardner, D. K. et al. Blastocyst development and birth after in-vitro maturation of human primary oocytes, intracytoplasmic sperm injection and assisted hatching. Hum Reprod 1995; 10(12):3243–7.CrossRefGoogle ScholarPubMed

Russell, J. B., Knezevich, K. M., Fabian, K. F. and Dickson, J. A. Unstimulated immature oocyte retrieval: early versus midfollicular endometrial priming. Fertil Steril 1997; 67(4):616–20.CrossRefGoogle ScholarPubMed

Lin, Y. H. and Hwang, J. L. In vitro maturation of human oocytes. Taiwan J Obstet Gynecol 2006; 45(2):95–9.Google Scholar

Lim, K. S., Chae, S. J., Choo, C. W., Ku, Y. H. et al. In vitro maturation: clinical applications. Clin Exp Reprod Med 2013; 40(4):143–7.CrossRefGoogle ScholarPubMed

Farsi, M. M., Kamali, N. and Pourghasem, M. Embryological aspects of oocyte in vitro maturation. Int J Mol Cell Med 2013; 2(3):99–109.Google Scholar

Chian, R. C., Buckett, W. M., Tulandi, T. and Tan, S. L. Prospective randomized study of human chorionic gonadotrophin priming before immature oocyte retrieval from unstimulated women with polycystic ovarian syndrome. Hum Replod 2000; 15(1):165–70.Google ScholarPubMed

Son, W. Y., Yoon, S. H. and Lim, J. H. Effect of gonadotrophin priming on in-vitro maturation of oocytes collected from women at risk of OHSS. Reprod Biomed Online 2006; 13(3):340–8.Google Scholar

Soderstrom-Anttila, V., Makinen, S., Tuuri, T. and Suikkari, AM. Favourable pregnancy results with insemination of in vitro matured oocytes from unstimulated patients. Hum Reprod 2005; 20(6):1534–40.Google Scholar

Son, W. Y., Chung, J. T., Demirtas, E., Helzer, H., et al. Comparison of in-vitro maturation cycles with and without in-vivo matured oocytes retrieved. Reprod Biomed Online 2008; 17(1):59–67.CrossRefGoogle ScholarPubMed

Son, W. Y., Chung, J. T., Chian, R. C., Herrero, B. et al. A 38 h interval between hCG priming and oocyte retrieval increase in vivo and in vitro oocyte maturation rate in programmed IVM cycles. Hum Reprod 2008; 23(9):2010–16.CrossRefGoogle ScholarPubMed

Son, W. Y. and Tan, S. L. Laboratory and embryological aspects of hCG-primed in vitro maturation cycles for patients with polycystic ovaries. Hum Reprod Update 2010; 16:675–89.CrossRefGoogle ScholarPubMed

Alpha Scientists in Reproductive Medicine, ESHRE Special Interest Group of Embryology. The Istanbul consensus workshop on embryo assessment: proceedings of an expert meeting. Reprod Biomed Online 2011; 22:632–46.Google Scholar

Alpha Scientists in Reproductive Medicine and ESHRE Special Interest Group of Embryology. The Istanbul consensus workshop on embryo assessment: proceedings of an expert meeting. Hum Reprod 2011; 26:1270–83.Google Scholar

Rienzi, L., Balaban, B., Ebner, T. and Mandelbaum, J. The oocyte. Hum Reprod 2012; 27: 2–21.CrossRefGoogle ScholarPubMed

Balaban, B. and Urman, B. Effect of oocyte morphology on embryo development and implantation. Reprod Biomed Online 2006; 12:608–15.CrossRefGoogle ScholarPubMed

Ebner, T. Is oocyte morphology prognostic of embryo developmental potential after ICSI? Reprod Biomed Online 2006; 12:507–12.Google Scholar

Balaban, B. and Ebner, T. Morphological selection of gametes and embryos: oocyte. In A Practical Guide to Selectiong Gametes and Embryos, ed. Montag, M (pp. 81–96) (Boca Raton, FL: CRC Press, Taylor & Francis Group, 2014).Google Scholar

ESHRE Task Force on Ethics and Law, including Dondorp, W., De Wert, G., Pennings, G. et al. Oocyte cryopreservation for age-related fertility loss. Hum Reprod 2012; 27:1231–7.Google Scholar

Practice Committees of the American Society for Reproductive Medicine and the Society for Assisted Reproductive Technology. Mature oocyte cryopreservation: a guideline. Fertil Steril 2013; 99:37–43.Google Scholar

Loren, A. W., Mangu, P. B., Beck, L. N. et al. Fertility preservation for patients with cancer: American Society of Clinical Oncology clinical practice guideline update. J Clin Oncol 2013; 31:2500–10.Google Scholar

Glujovsky, D., Riestra, B., Sueldo, C. et al. Vitrification versus slow freezing for women undergoing oocyte cryopreservation (review). Cochrane Database Syst Rev 2014; 5(9):CD010047.Google Scholar

Chen, C. Pregnancy after human oocyte cryopreservation. Lancet 1986; 1:884–6.Google Scholar

Martinez-Burgos, M., Herrero, L., Megias, D. et al. Vitrification versus slow freezing of oocytes: effects on morphologic appearance, meiotic spindle configuration, and DNA damage. Fertil Steril 2011; 95:374–7.CrossRefGoogle ScholarPubMed

Dominguez, F., Castello, D., Remohi, J. et al. Effect of vitrification on human oocytes: a metabolic profiling study. Fertil Steril 2013; 99:565–72.CrossRefGoogle ScholarPubMed

Noyes, N., Porcu, E., Borini, A. et al. Over 900 oocyte cryopreservation babies born with no apparent increase in congenital anomalies. Reprod Biomed Online 2009; 18:769–76.Google Scholar

Vajta, G., Rienzi, L. and Ubaldi, F. Open versus closed systems for vitrification of human oocytes and embryos. Reprod Biomed Online 2015; 325–33.Google Scholar

Kuwayama, M. Highly efficient vitrification for cryopreservation of human oocytes and embryos: the Cryotop method. Theriogenology 2007; 67:73–80.CrossRefGoogle ScholarPubMed

Directive 2004/23/EC of the European Parliament and of the Council of 31 March 2004 on Setting Standards of Quality and Safety for the Donation, Procurement, Testing, Processing, Preservation, Storage and Distribution of Human Tissues and Cells. Official Journal of the European Union 2004; L 102/48–58.Google Scholar

Commission Directive 2006/17/EC of 8 February 2006 Implementing Directive 2004/23/EC of the European Parliament and of the Council as Regards Certain Technical Requirements for the Donation, Procurement and Testing of Human Tissues and Cells. Official Journal of the European Union 2006; L 38/40–52.Google Scholar

Commission Directive 2006/86/EC of 24 October 2006 Implementing Directive 2004/23/EC of the European Parliament and of the Council as Regards Traceability Requirements, Notification of Serious Adverse Reactions and Events and Certain Technical Requirements for the Coding, Processing, Preservation, Storage and Distribution of Human Tissues and Cells. Official Journal of the European Union 2006; L 294/32–50.Google Scholar

Parmegiani, L., Cognigni, G. E. and Filicori, M. Ultra-violet sterilization of liquid nitrogen prior to vitrification. Hum Reprod 2009; 24:2969.Google Scholar

Parmegiani, L. and Rienzi, L. Hermetical goblets for cryostorage of human vitrified specimens. Hum Reprod 2011; 26:3204.Google Scholar

Cobo, A., Romero, J. L., de Los Santos, M. J. et al. Storage of human oocytes in the vapor phase of nitrogen. Fertil Steril 2010; 94:1903–7.Google Scholar

Cobo, A., Meseguer, M., Remohi, J., et al. Use of cryobanked oocytes in an ovum donation programme: a prospective, randomized, controlled, clinical trial. Hum Reprod 2010; 25:2239–46.CrossRefGoogle Scholar

Rienzi, L., Romano, S., Albricci, A., et al. Embryo development of fresh versus ‘vitrified’ metaphase II oocytes after ICSI: a prospective randomized sibling-oocyte study. Hum Reprod 2010; 25:66–73.CrossRefGoogle ScholarPubMed

Rienzi, L., Cobo, A., Paffoni, A. et al. Consistent and predictable delivery rates after oocyte vitrification: an observational longitudinal cohort multicentric study. Hum Reprod 2012; 27:1606–12.CrossRefGoogle ScholarPubMed

Cobo, A., Garrido, N., Crespo, J. et al. Accumulation of oocytes: a new strategy for managing low-responder patients. Reprod Biomed Online 2012; 24:424–32.CrossRefGoogle ScholarPubMed