P-14 Immediate insemination of human oocytes by IVF or ICSI does not reduce fertilization rates
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sarily exclude some minority of cases where shortening the incu- bation time might help. The possibility exist that the hypothesis that toxic sperm factors are operative and do impair implantation related to the large sperm insemination concentration is real but shortening the incubation time does not override the abnormality. PI1 SOO15- 0282(99)00047-3 P-13 Gestational Surrogacy Greatly Enhances Pregnancy and Im- plantation Rates in Both Fresh and Frozen Embryo Transfers. CA. Adams, L.A. Anderson, C. Montgomery, B. Hansen, S.H. Wood. The Reproductive Sciences Center, La Jolla, CA. Objectives: Studies have indicated that gestational surrogacy results in high pregnancy rates; however, whether this is primarily due to differences in uterine receptivity or embryo quality is un- clear. An evaluation of fresh and frozen embryo transfers in surro- gate and non-surrogate IVF/ICSI cycles was undertaken to examine this issue. Design: A retrospective study of IVF/lCSI fresh and frozen embryo transfer (FET) cycles performed during a one year period was conducted. Surrogate and non-surrogate cycles were compared with respect to age of oocyte donor/patient (for FET cycles, age when embryos were frozen), age of embryo recipient (surrogate/ patient), number of embryos transferred, quality of embryos trans- ferred, clinical pregnancy rates and implantation rates. Results: A total of 163 cycles were evaluated and divided into four groups: (a) 113 fresh embryo transfers into non-surrogates, (b) 30 FETs into non-surrogates, (c) 10 fresh embryo transfers into surrogates and (d) 10 FETs into surrogates. As expected, surrogates were significantly younger (mean age 30 years) than the non- surrogates receiving embryos (mean=36 years; P<.Ol); however there were no significant differences in the mean age of the recip- ients of fresh or frozen embryos in either of these groups. The mean age of oocyte donor/patient, number of embryos transferred, and quality of embryos transferred were not significantly different across these four groups. Clinical pregnancy rates for each group were as follows: (a) 59%, (b) 33%, (c) 90%, and (d) 70%. The implantation rates for each group were as follows: (a) 19%, (b) 13%, (c) 42%, and (d) 27%. Conclusions: Pregnancy and implantation rates are greatly en- hanced in both fresh and frozen embryo transfer cycles utilizing gestational surrogates as compared to non-surrogates. Because the uterine environment into which embryos are transferred in fresh surrogate and non-surrogate cycles differ significantly, it is not possible to determine if the enhanced pregnancy rate seen is simply due to a more optimal surrogate uterine hormonal milieu. Since this confounding variable is eliminated in FET cycles, the markedly improved pregnancy rates noted in this type of cycle strongly suggests that other aspects of uterine receptivity play an important role in the enhanced implantation rate seen in surrogate cycles. It is possible that surrogacy may benefit patients with unexplained in- fertility who have failed multiple ART cycles. PII SOO15- 0282(99)00048-5 P-14 Immediate Insemination of Human Oocytes by IVF or ICSI Does Not Reduce Fertilization Rates. C.A. Adams, L.S. Ander- son, B. Hansen, S.H. Wood. The Reproductive Sciences Center, La Jolla, CA. Objective: Early IVF studies suggest that fertilization rates are enhanced when metaphase II oocytes are cultured for 4-6 hours prior to insemination to allow complete nuclear and cytoplasmic maturation. The aim of this study was to compare IVF and ICSI fertilization rates with and without a 4-6 hour preincubation pe- riod. Design: 326 consecutive ART procedures performed during a 2-year period were assessed retrospectively. All IVF and ICSI procedures were performed in a consistent manner by the same laboratory staff members. Data was analyzed using the unpaired t-test. Results: 137 IVF procedures were reviewed: Group (a) 70 cases in which oocytes were cultured at least 4 hours prior to insemina- tion and group (b) 67 cases in which sperm was added within 2 hours of oocyte recovery. Mean age of patients in both groups was 34 years. A total of 555 oocytes were inseminated in (a) resulting in a total fertilization rate of 81% (75% 2PN, 6% 3PN). In (b) with 3 17 oocytes, total fertilization rate was 80%, (78% 2PN, 3% 3PN). 189 ICSI procedures were examined: Oocytes were either in- jected after at least 4 hours incubation (105 cases; group c) or within 3 hours of retrieval (84 cases; group d). Mean patient age (34 years) was the same in (c) and (d). 1254 oocytes were inseminated in group (c) resulting in a total fertilization rate of 68%, (67% 2PN, 2% 3PN). In group (d) 800 oocytes were inseminated resulting in 69% fertilization (67% 2PN, 2% 3PN). Clinical pregnancy rates per embryo transfer in the four groups were: (a) 34%, (b) 51%, (c) 42%, and (d) 43% indicating no decrease in IVF or ICSI pregnancy rates when insemination was performed immediately after oocyte retrieval. Conclusion: Preincubation of oocytes prior to IVF or ICSI in- semination did not affect fertilization rates, therefore, insemination of metaphase II oocytes by IVF or KS1 may be performed imme- diately after oocyte retrieval. In terms of IVF pregnancy rates, it may even be beneficial to inseminate oocytes soon after retrieval. Such flexibility allows embryologists to maximize work efficiency in addition to providing optimal ART results. PI1 SOO15-0282(99) 00049-7 P-15 IncreasedEmbryo Transfer Pregnancy Rates Using Assisted Hatching on Day 3 Frozen-Thawed Embryos. M.C. Schiewe, G.E. Ringler, R.P. Marrs, A.L. Stein, J.M. Varygas, J. Greene. California Fertility Associates/Institute for Fertility Research, Santa Monica, CA. The effectiveness of assisted hatching (AH) to overcome hatch- ing defects in preimplantation stage embryos in select patient groups varies between IVF programs. Surprisingly, few published reports exist relative to AH of cryopreserved embryos where alter- ations in zona pellucida properties or the embryonic production of a zona lysin would more likely occur. The objective of this pro- spective study (initiated in January 1998) was to evaluate the efficiency of AH to promote the establishment of pregnancy in human IVF/ICSI patients (n=88) whose frozen-thawed embryos were cryopreserved at the two pronucleate or 2- to 8-cell stage. Good to excellent quality embryos underwent a 3-step dilution into 1.5M propylene glycol + 0.2M sucrose, placed in 0.5 mL straws and cooled at 0.3YXnin from -5°C (seeding temperature) to -30°C before cryostored in liquid nitrogen. Thawed embryos were diluted in 0.2M and O.lM sucrose solutions, washed in H-HTF + SSS and then cultured in 0.1 mL microdrops of D3 medium (Conception Tech., San Diego, CA) + 10% SSS under oil in a 5%CO, humid- ifled atmosphere at 37°C. Control transfers were performed (n=49 patients) or AH, using acidic Tyrodes solution, was conducted FERTILITY & STERILITY@ 17s
Transcript of P-14 Immediate insemination of human oocytes by IVF or ICSI does not reduce fertilization rates
sarily exclude some minority of cases where shortening the incu- bation time might help. The possibility exist that the hypothesis that toxic sperm factors are operative and do impair implantation related to the large sperm insemination concentration is real but shortening the incubation time does not override the abnormality. PI1 SOO15- 0282(99)00047-3
P-13
Gestational Surrogacy Greatly Enhances Pregnancy and Im- plantation Rates in Both Fresh and Frozen Embryo Transfers. CA. Adams, L.A. Anderson, C. Montgomery, B. Hansen, S.H. Wood. The Reproductive Sciences Center, La Jolla, CA.
Objectives: Studies have indicated that gestational surrogacy results in high pregnancy rates; however, whether this is primarily due to differences in uterine receptivity or embryo quality is un- clear. An evaluation of fresh and frozen embryo transfers in surro- gate and non-surrogate IVF/ICSI cycles was undertaken to examine this issue.
Design: A retrospective study of IVF/lCSI fresh and frozen embryo transfer (FET) cycles performed during a one year period was conducted. Surrogate and non-surrogate cycles were compared with respect to age of oocyte donor/patient (for FET cycles, age when embryos were frozen), age of embryo recipient (surrogate/ patient), number of embryos transferred, quality of embryos trans- ferred, clinical pregnancy rates and implantation rates.
Results: A total of 163 cycles were evaluated and divided into four groups: (a) 113 fresh embryo transfers into non-surrogates, (b) 30 FETs into non-surrogates, (c) 10 fresh embryo transfers into surrogates and (d) 10 FETs into surrogates. As expected, surrogates were significantly younger (mean age 30 years) than the non- surrogates receiving embryos (mean=36 years; P<.Ol); however there were no significant differences in the mean age of the recip- ients of fresh or frozen embryos in either of these groups. The mean age of oocyte donor/patient, number of embryos transferred, and quality of embryos transferred were not significantly different across these four groups. Clinical pregnancy rates for each group were as follows: (a) 59%, (b) 33%, (c) 90%, and (d) 70%. The implantation rates for each group were as follows: (a) 19%, (b) 13%, (c) 42%, and (d) 27%.
Conclusions: Pregnancy and implantation rates are greatly en- hanced in both fresh and frozen embryo transfer cycles utilizing gestational surrogates as compared to non-surrogates. Because the uterine environment into which embryos are transferred in fresh surrogate and non-surrogate cycles differ significantly, it is not possible to determine if the enhanced pregnancy rate seen is simply due to a more optimal surrogate uterine hormonal milieu. Since this confounding variable is eliminated in FET cycles, the markedly improved pregnancy rates noted in this type of cycle strongly suggests that other aspects of uterine receptivity play an important role in the enhanced implantation rate seen in surrogate cycles. It is possible that surrogacy may benefit patients with unexplained in- fertility who have failed multiple ART cycles. PII SOO15- 0282(99)00048-5
P-14
Immediate Insemination of Human Oocytes by IVF or ICSI Does Not Reduce Fertilization Rates. C.A. Adams, L.S. Ander- son, B. Hansen, S.H. Wood. The Reproductive Sciences Center, La Jolla, CA.
Objective: Early IVF studies suggest that fertilization rates are enhanced when metaphase II oocytes are cultured for 4-6 hours prior to insemination to allow complete nuclear and cytoplasmic maturation. The aim of this study was to compare IVF and ICSI fertilization rates with and without a 4-6 hour preincubation pe- riod.
Design: 326 consecutive ART procedures performed during a 2-year period were assessed retrospectively. All IVF and ICSI procedures were performed in a consistent manner by the same laboratory staff members. Data was analyzed using the unpaired t-test.
Results: 137 IVF procedures were reviewed: Group (a) 70 cases in which oocytes were cultured at least 4 hours prior to insemina- tion and group (b) 67 cases in which sperm was added within 2 hours of oocyte recovery. Mean age of patients in both groups was 34 years. A total of 555 oocytes were inseminated in (a) resulting in a total fertilization rate of 81% (75% 2PN, 6% 3PN). In (b) with 3 17 oocytes, total fertilization rate was 80%, (78% 2PN, 3% 3PN).
189 ICSI procedures were examined: Oocytes were either in- jected after at least 4 hours incubation (105 cases; group c) or within 3 hours of retrieval (84 cases; group d). Mean patient age (34 years) was the same in (c) and (d). 1254 oocytes were inseminated in group (c) resulting in a total fertilization rate of 68%, (67% 2PN, 2% 3PN). In group (d) 800 oocytes were inseminated resulting in 69% fertilization (67% 2PN, 2% 3PN).
Clinical pregnancy rates per embryo transfer in the four groups were: (a) 34%, (b) 51%, (c) 42%, and (d) 43% indicating no decrease in IVF or ICSI pregnancy rates when insemination was performed immediately after oocyte retrieval.
Conclusion: Preincubation of oocytes prior to IVF or ICSI in- semination did not affect fertilization rates, therefore, insemination of metaphase II oocytes by IVF or KS1 may be performed imme- diately after oocyte retrieval. In terms of IVF pregnancy rates, it may even be beneficial to inseminate oocytes soon after retrieval. Such flexibility allows embryologists to maximize work efficiency in addition to providing optimal ART results. PI1 SOO15-0282(99) 00049-7
P-15
Increased Embryo Transfer Pregnancy Rates Using Assisted Hatching on Day 3 Frozen-Thawed Embryos. M.C. Schiewe, G.E. Ringler, R.P. Marrs, A.L. Stein, J.M. Varygas, J. Greene. California Fertility Associates/Institute for Fertility Research, Santa Monica, CA.
The effectiveness of assisted hatching (AH) to overcome hatch- ing defects in preimplantation stage embryos in select patient groups varies between IVF programs. Surprisingly, few published reports exist relative to AH of cryopreserved embryos where alter- ations in zona pellucida properties or the embryonic production of a zona lysin would more likely occur. The objective of this pro- spective study (initiated in January 1998) was to evaluate the efficiency of AH to promote the establishment of pregnancy in human IVF/ICSI patients (n=88) whose frozen-thawed embryos were cryopreserved at the two pronucleate or 2- to 8-cell stage. Good to excellent quality embryos underwent a 3-step dilution into 1.5M propylene glycol + 0.2M sucrose, placed in 0.5 mL straws and cooled at 0.3YXnin from -5°C (seeding temperature) to -30°C before cryostored in liquid nitrogen. Thawed embryos were diluted in 0.2M and O.lM sucrose solutions, washed in H-HTF + SSS and then cultured in 0.1 mL microdrops of D3 medium (Conception Tech., San Diego, CA) + 10% SSS under oil in a 5%CO, humid- ifled atmosphere at 37°C. Control transfers were performed (n=49 patients) or AH, using acidic Tyrodes solution, was conducted
FERTILITY & STERILITY@ 17s
