JE Lee, DR Lee, HR Paik, HN Shim, SH Lee, JH Cho, SI Roh, HS Yoon. Biochemical assisted hatching(BHA) by pronase increased the pregnacy rate in human ART program. International Session of the 51st JSOG Meeting 1999.

BR Do, JH Choi, JH Cho, CJ Lee, SI Roh, HS Yoon. Structural changes and steroidogenesis in frozen-thawed 18 weeks human fetal ovarian tissue during in vitro culture. 54h Annual Meetings American Society for Reproductive Medicine 1998.

BR Do, CJ Lee, JH Cho, HS Yoon. In vitro growth of primordial follicular oocyte in the frozen-thawed ovarian tissue of neonatal mouse. 54th Annual Meetings American Society for Reproductive Medicine 1998.

DR Lee, JW Kim, YJ Lim, JE Lee, JH Cho, SI Roh, HS Yoon. Analysis of fertilization, embryonic development and pregnancy rate after ICSI using spermatozoa obtained from fresh or frozen-thawed testicular tissues. 54th Annual Meetings American Society for Reproductive Medicine 1998.

JH Cho, BR Do, DR Lee, SJ Yoon, HR Paik, SI Roh. Assisted reproductive technology program by immature oocyte retrieval in nonstimulated cycle. 54th Annual Meetings American Society for Reproductive Medicine 1998.

HS Yoon, JH Lee, JT Seo, HJ Kim, DR Lee, JS Jeon, JH Cho, SI Roh. The Incidence of microdeletion and the frequency of AZFa, b, c deletion in male infertility patients. 53th Annual Meetings American Society for Reproductive Medicine 1997.

JE Lee, DR Lee, HR Paik, HC Kim, HN Shim, SH Lee, JH Cho, SI Roh, HS Yoon. Application of biochemical assisted hatching(BAH) by protease in human assisted reproductive technology program. 56th Annual Meetings American Society for Reproductive Medicine 1997.

DR Lee, YJ Lim, HS Yoon, JH Lee, JT Seo, JS Jeon, HN Shim, JH Cho, SI Roh. Application of ICSI or RoSI by testicular biopsy in non-obstructive azoospermia. 53th Annual Meetings American Society for Reproductive Medicine 1997.

DR Lee, YJ Lim, JW Kim, SJ Yoon, HS Yoon, JS Jeon, HW Min, JH Cho, SI Roh. Detailed semen analysis and ICSI in azoospermia-like infertile patients. 53th Annual Meetings American Society for Reproductive Medicine 1997.

DR Lee, JH Lee, HN Shim, JT Seo, JS Jeon, JH Cho, SI Roh. and HS Yoon. Identification of round spermatid from testis biopsy and its application in human ART program. 10th World Congress on In Vitro Fertilization and Assisted Reproduction 1997.

HS Yoon, JH Lee, JT Seo, HJ Kim, DR Lee, JS Jeon, JH Cho, MK Kim, MS Lee, SI Roh. Microdeletion of Y chromosome in Korean male infertility patient. 5th International Congress of Andrology, 1997

SI Roh, DR Lee, HR Paik, JE Lee, HC Kim, HN Shim, JH Cho, HS Yoon. Biochemical assisted hatching by proteases increased pregnancy rates in human IVF-ET program. 52th Annual Meetings American Society for Reproductive Medicine 1996.