Since the oocyte maturation level is one of the major variables which impacts the total available number of oocytes for vitrification, it is also important to know if low oocyte maturity would impact the clinical outcomes after oocyte vitrification. Therefore, this study was to assess the influence of oocyte maturation level on IVF outcomes when using donor oocyte cryo-banking. Longitudinal observational study. Cryopreservation on donor oocytes (262 donation cycles) was performed by minimum volume vitrification method. Oocytes were warmed for each matched recipient independently (658 recipient cycles). Data were tabulated as: I)<60% oocyte maturity at retrieval, II) 60-80% oocyte maturity at retrieval, III)>80% oocyte maturity at retrieval. Outcome parameters were analyzed by the One-way ANOVA or the Chi-square tests, as appropriate (P<0.05).Tabled 1RESULTS:Group (Oocyte maturity at retrieval)I (<60%)II (60-80%)III (>80%)P Value# donation cycle32122108-Age of donor26.84±3.2326.32±2.7725.75±2.73NSE22700±12943007±17182918±1904NSDate of trigger12.15±1.0812.27±1.4312.22±1.27NS# of egg retrieved890 (27.81±8.85)3764 (30.85±13.66)2928 (27.11±12.19)NSMaturity (%)472 (53.05±5.93)a2712 (71.96±5.75)b2589 (88.96±5.84)cP<0.05# recipient cycle64315279-Age of recipient41.76±4.8341.47±4.4740.95±4.46NS# total egg warmed378(5.90±1.17)1949(6.18±1.84)1699(6.08±1.86)NS# survived (%)338 (89.41)1727 (88.60)a1544 (90.87)bP<0.05# fertilized (%)307 (81.21)1490 (76.44)1323 (77.86)NS# ET108 (1.68±0.53)538 (1.70±0.55)456 (1.63±0.53)NS#Clinical Pregnancy (%)42 (65.62)205 (65.67)172 (61.64)NS# Implantation (%)57 (52.77)274 (50.92)211 (46.27)NSa,b,cSignificantly different (P<0.05). Open table in a new tab a,b,cSignificantly different (P<0.05). This study demonstrates that the low oocyte maturity is not associated with decreased clinical outcomes after oocyte vitrification. Thus, the above findings suggested that the oocyte quality remained high even when the vitrified oocytes were retrieved from the low maturity group.

Oocyte cryopreservation by vitrification has proven to be an efficient approach, however there is limited data available on the safety of this technology. For this reason we collected and analyzed live birth outcomes obtained after egg freezing for all recipients in a frozen donor egg recipient program. Retrospective data analysis. From December 2006 to June 2011, live birth outcomes from 257 deliveries following vitrified donation cycles were analyzed. All oocytes were vitrified/warmed and transferred using a standardized technique. All inseminations were performed by ICSI. If HCG was positive, fetal cardiac activity was measured by ultrasound 6-7 weeks after transfer. A total of 514 patients underwent an embryo transfer. An average of 1.76 (±0.52) embryos were transferred. A total of 316 patients had a clinical pregnancy of which 257 have already delivered.Tabled 1Live Birth Outcomes# of patients / Deliveries257Recipient Age41.3 ± 4.47Donor Age26.7 ± 2.90Live births (infants born)338Term delivery 37 wk188Congenital anomaly*Congenital anomalies: Heart murmur, 1 baby died at 2 months (multiple complications), Cleft lip / palate, Club foot, Spina bifida (TAB)5Weight in gr. (mean +/-SD); All deliveries2938.3 ± 770.0# of Singleton/twin/triplet deliveries (# of live births)178 (178) / 77 (154) / 2(6)Weight in gr. (mean +/-SD) Singleton, Term deliveries (n=156)3518.8 ± 585.2* Congenital anomalies: Heart murmur, 1 baby died at 2 months (multiple complications), Cleft lip / palate, Club foot, Spina bifida (TAB) Open table in a new tab These live birth data suggest that vitrification, as a method of choice for cryopreserving oocytes, does not correlate with higher incidence of adverse outcomes when compared with a fresh IVF population (Bondelle, M. et al. Human Reproduction. Vol.17, No.3 pp. 671-694, 2002). The most frequently observed undesirable outcome was the high incidence of multiple (especially, twin) birth delivery. This study thus indicates that oocyte vitrification may be a relatively safe method for cryo-storage of the female gamete and a valuable treatment option for egg donation purposes.

To evaluate the cumulative pregnancy and implantation rates (per thawed egg) obtained from cryopreserved donor oocytes. Retrospective data analysis. Outcome parameters were computed from 676 egg warming and 81 subsequent embryo warming cycles; using a total of 4163 donor oocytes to warm. The vitrification procedure was performed using a 30% mix of DMSO and Ethylene glycol applying the minimal volume approach with carriers of Cryotop ™ or Cryolock ™. Clinical pregnancy was established by ultrasound detection of fetal cardiac activity 6-7 weeks after transfer. 1273 embryos were transferred in a total of 757 cycles (egg warming and/or embryo warming together). Cumulative pregnancy rate was 66.7% (egg and embryo warming). Implantation rate per oocyte warmed was 15.8%. Details of the egg and embryo warming cycles are summarized in the following table.Tabled 1Summary of egg /embryo warming cycles.Egg WarmingEmbryo WarmingRecipient cycles67681No. of eggs/embryos warmed4163 (6.1±1.8)153 (1.9±0.8)Survival rate89.5%97.3%Fertilization rate86.2%-Blastocyst rate62.7%-No. of embryos transferred1134 (1.68±0.73)139 (1.72±0.64)No. of clinical pregnancies43570Clinical pregnancy rate64.3%86.4%FCA's56692Implantation rate49.9%66.1%Implantation rate per oocyte/embryo warmed13.5%60.1% Open table in a new tab This study demonstrates that oocyte vitrification is a highly viable technique that can be used efficiently for oocyte donation programs. High pregnancy and implantation rates are further enhanced by the resourceful use of supernumerary embryos cryopreserved from the initial egg warming cycles. When calculated from the cumulative results (egg warming and embryo warming together), 15.8% of the warmed donor oocytes have proven to be viable, by being able to implant.

To evaluate the efficiency of single and multiple embryo transfers in a donor-recipient program using vitrified/warmed oocytes. Retrospective study. A total of 5014 MII oocytes were obtained and vitrified from 225 donors who were screened and tested according to FDA and ASRM guidelines. Eggs were vitrified 3-4 h after retrieval using minimal volume method. ICSI was performed 2-3 h after warming. Embryos were evaluated morphologically prior to transfer, and when high quality embryos were observed the recipient had the possibility of a single embryo transfer. Clinical and laboratory parameters were analyzed using the One-way ANOVA and the Fisher's exact test at the level of P<0.05. Donors mean age was 26.1 ± 2.7 years.Tabled 1Single-ETMulti-ETPNo. of recipients126351Recipient age (mean ± SD)42.2 ± 4.240.7 ± 4.4<0.01No. of oocytes warmed (mean ± SD)711 (5.6 ± 1.8)2238 (6.4 ± 2.0)<0.01No. of oocytes survived (%)643 (90.4)1957 (87.4)0.04No. of oocytes fertilized (%)560 (78.8)1707 (76.3)NSNo. of good quality embryos on Day3 (mean ± SD)380 (3.0 ± 1.6)1040 (3.0 ± 1.4)NSNo. of blastocysts (mean ± SD)*Only for Day-5 ET cases (113 for SET and 274 for MET).396 (3.5 ± 1.5)976 (3.6 ± 1.5)NSNo of embryos for ET (mean ± SD)126725NANo. of embryos re-vitrified (mean ± SD)265 (2.1 ± 1.5)356 (1.0 ± 1.3)<0.05No. clinical pregnancies (%)77 (61.1)211 (60.1)NSNo. of implantations (%)78 (61.9)317 (43.7)<0.05There were 105 (49.8%) pregnancies with multiple implantations in the MET group, while there was only one twin pregnancy (due to monozygotic twinning) in the SET group (P<0.001).* Only for Day-5 ET cases (113 for SET and 274 for MET). Open table in a new tab There were 105 (49.8%) pregnancies with multiple implantations in the MET group, while there was only one twin pregnancy (due to monozygotic twinning) in the SET group (P<0.001). The outcome of the current study shows that SET of vitrified/warmed donor oocytes provides both high implantation rates (and virtually no risks for multiples) and high pregnancy rates similar to multiple embryo transfers. Thus, SET should be recommended when high quality embryo(s) are available for qualifying patients to achieve safe pregnancy outcomes.

To investigate the ongoing oocyte to implantations and baby rate in a donor/recipient program using oocytes banked by vitrification. Retrospective analysis of clinical and embryological database. A total of 290 recipients of oocyte donation cycles from 88 donors (112 cycles) who banked a total of 2078 MII oocytes by vitrification were analyzed. Main outcomes measured were the total number of metaphase II oocytes vitrified/rewarmed, the number of embryos transferable (fresh and frozen) and the corresponding oocyte to ongoing implantation (beyond week 12) or live baby born (LBB) rates. In patients with remaining frozen embryos, the final LBB was estimated according to our reported rates. The 2078 oocytes vitrified were obtained from donors of mean age 26.1 and the average oocyte/cycle was 18.5. Of the 1772 oocytes rewarmed, 1559 (88%) survived, 1169 (75%) fertilized and 914 (51%) resulted in cleaved, usable embryos of which 519 were transferred (mean of 1.8 per recipient) and 395 were frozen.Tabled 1SummaryTotal MII vitrifiedWarmedSurvivedUsable EmbryoEmbryos TransferredOngoing/ DeliveredLBB/ OocyteRecipients (290)20781772155991451920311.4%Mean20.2/donor6.15.33.11.8SD9.11.81.41.30.5Donors (88)Retrievals (112)mean18.5 Open table in a new tab After 290 transfers in recipients, the total ongoing implantations and LBB per oocyte and per embryo transferred were 11% and 39%, respectively. By using the additional cryopreserved oocytes (n = 306) and embryos (n = 395), the estimated total LBB rate per oocyte was 16% (332/2078) and per total embryos transferred was 32% (332/1030). The analysis of this study reveals that a) Vitrification is a very efficient cryopreservation system; b) Oocyte banking is an effective tool to simplify the process of egg donation; c) The total oocyte to baby rate of 16%, similar to that published with fresh donor oocytes when adjusted for MII, can be considered the best parameter against which to measure biological competence.

Egg donation has become a useful option for infertility treatment. Once a donor had a successful donation cycle, she may opt to return for subsequent donations. The purpose of this study was to compare egg quality, vitrification tolerance and developmental potential between 1st, 2nd and 3rd donations. Retrospective study. Data were collected over a 3-year period. Variables were number of eggs retrieved per donation, percentage of MII, MI and GV stage eggs, survival after warming, fertilization, cleavage, blastocyst and implantation rate (fetal cardiac activity per embryo transferred). Comparison of means was performed using the Kruskal-Wallis test (P≤0.05 considered significant). Data indicates no differences between 1st, 2nd and 3rd donations for cohort-related variables (# eggs retrieved, % MII, % MI and % GV eggs, data not shown) or recipient cycle-related variables.Tabled 1Survival and development after ICSI of eggs from sequential donation cycles.Variable1st donationsA2nd donationsB3rd donationsC% Survived93.9 ± 1.0693.5 ± 1.2581.8 ± 7.65% Fertilized87.8 ± 1.7289.7 ± 1.4882.6 ± 9.76% Cleaved86.7 ± 1.7785.2 ± 2.0682.6 ± 8.73% Blastocyst53.7 ± 2.8959.0 ± 3.5862.2 ± 11.53% Implantation*45.7 ± 4.3957.0 ± 5.2345.5 ± 12.53Data presented as mean ± S.E.M. An = 97, Bn = 75, Cn = 13. No statistical differences were observed between 1st, 2nd and 3rd donations for any of the variables (P≤0.05). * Some data points for implantation rate are pending and were omitted. nimp.1 = 90, nimp.2 = 71, nimp.3 = 11. Open table in a new tab Data presented as mean ± S.E.M. An = 97, Bn = 75, Cn = 13. No statistical differences were observed between 1st, 2nd and 3rd donations for any of the variables (P≤0.05). * Some data points for implantation rate are pending and were omitted. nimp.1 = 90, nimp.2 = 71, nimp.3 = 11. Results imply that sequential donations have no significant negative effect on egg quality, survivability or developmental potential. Donors with successful first cycles can thus be encouraged to return for subsequent donations. Results may be valuable to potential donors concerned about the effects of egg donation on subsequent fertility. Research on natural reproductive performance of egg donors later in life will be valuable to give more clarity on the subject.

OBJECTIVE: Our objective was to compare oocyte vitrification outcomes with vitrification solution containing single permeable cryoprotectant (Ethylene glycol (EG)) vs. mixture of permeable cryoprotectants (EG and Dimethyl sulfoxide (DMSO)).DESIGN: Prospective study.MATERIALS AND METHODS: Cryopreservation on sibling oocytes from 28 donors was performed by minimum volume vitrification method. Donor sibling oocytes were divided into two groups for vitrification: mixtures of permeable cryoprotectants (15% EG and 15% DMSO; group A) vs. single permeable cryoprotectant (30% EG; group B). Sibling oocytes from both groups were warmed at the same time for each recipient (N=52). Oocytes were fertilized by ICSI 2-3 hours after warming. On day 5, blastocyst formation was assessed and embryo transfer was performed. Results were analyzed by Fisher's exact test (P<0.05).Tabled 1A (EG + DMSO)B (EG)Recipient age (N=52)41.0 ± 4.9Donor age (N=28)27.0 ± 2.9# of oocyte warmed216133# of oocyte survived (%)∗Significantly different (P<0.05).193/216 (89.3)128/133 (96.2)# of oocyte fertilized (%)175/216 (81.0)109/133 (81.9)# of blastocyst (%)124/216 (57.4)71/133 (53.4)# of embryo transferred (%)62/216 (28.7)41/133 (30.8)# of embryo re-vitrified (%)62/216 (28.7)30/133 (22.6)# of ET (mean ± SD)1.98 ± 0.3Clinical pregnancy rate (%)29 (55.8)Implantation rate (%)48/103 (46.5)# of delivery8# of live birth14∗ Significantly different (P<0.05). Open table in a new tab CONCLUSION: These data suggested that using single permeable cryoprotectant (EG) in the vitrification solutions had better oocyte survival than the mixtures of cryoprotectants (EG + DMSO). We also demonstrated that the fertilization and blastocyst rates were similar between single and mixtures of permeable cryoprotectant. The data presented here suggest a vitrification solution with only one permeable cryoprotectant can provide equivalent efficacy and efficiency of oocyte vitrification to a common protocol that contains cryoprotectant mixtures. OBJECTIVE: Our objective was to compare oocyte vitrification outcomes with vitrification solution containing single permeable cryoprotectant (Ethylene glycol (EG)) vs. mixture of permeable cryoprotectants (EG and Dimethyl sulfoxide (DMSO)). DESIGN: Prospective study. MATERIALS AND METHODS: Cryopreservation on sibling oocytes from 28 donors was performed by minimum volume vitrification method. Donor sibling oocytes were divided into two groups for vitrification: mixtures of permeable cryoprotectants (15% EG and 15% DMSO; group A) vs. single permeable cryoprotectant (30% EG; group B). Sibling oocytes from both groups were warmed at the same time for each recipient (N=52). Oocytes were fertilized by ICSI 2-3 hours after warming. On day 5, blastocyst formation was assessed and embryo transfer was performed. Results were analyzed by Fisher's exact test (P<0.05). CONCLUSION: These data suggested that using single permeable cryoprotectant (EG) in the vitrification solutions had better oocyte survival than the mixtures of cryoprotectants (EG + DMSO). We also demonstrated that the fertilization and blastocyst rates were similar between single and mixtures of permeable cryoprotectant. The data presented here suggest a vitrification solution with only one permeable cryoprotectant can provide equivalent efficacy and efficiency of oocyte vitrification to a common protocol that contains cryoprotectant mixtures.

OBJECTIVE: Since oocyte vitrification offers major potential for both donor cryo-banking and fertility preservation, it is important to know if the cryo-storage duration would not impair viability of the vitrified oocytes. Therefore, our objective was to assess the influence of cryo-storage duration on the vitrified oocyte in the oocyte donation cycles using oocyte cryo-banking. DESIGN: Parallel-group study. MATERIALS AND METHODS: Cryopreservation on donor sibling oocytes (from 10 donation cycles) was performed by minimum volume vitrification method. Sibling oocytes were warmed for each matched recipient independently (20 recipients). Data were tabulated as: A) First warm group (less than 6 month cryo-storage), B) Second warm group (over 6 month of cryo-storage). Outcome parameters were analyzed by the One-way ANOVA or the Fisher's exact tests, as appropriate (P<0.05). RESULTS: Below.Tabled 1A (First warm)B (Second warm)P value# of donor (mean age ± SD)10 (25.2 ± 2.7)NA# of recipient (mean age ± SD)10 (41.9 ± 2.1)10 (41.0 ± 2.9)NSMean storage duration (month)3.35 ± 1.020.65 ± 3.9<0.05# of oocyte warmed (mean ± SD)62 (6.2 ± 1.1)65 (6.5 ± 2.5)NS# of oocyte survived (%)53 (85.4)53 (81.5)NS# of oocyte fertilized (%)48 (90.5)46 (86.8)NS# of embryo cleaved (%)48 (100)44 (95.6)NS# of blastocyst (%)30/48 (62.5)19/40 (47.5)NS# of ET (mean ± SD)21 (2.1 ± 0.57)19 (1.9 ± 0.56)NS# of Clinical PR(%)8 (80.0)5 (50.0)NS# of Implantation (%)12/21 (57.1)9/19 (47.3)NS Open table in a new tab CONCLUSION: The results indicated that all measured parameters were comparable between two groups. We have also demonstrated that the extended cryo-storage duration (well over 6 month) of vitrified oocytes did not compromise the resulting oocyte quality, embryo development, and clinical outcome. Thus, the above findings suggest that vitrification of oocytes may remain efficient if a quarantine period of six month is applied or when it is used for fertility preservation.

OBJECTIVE: To evaluate laboratory and clinical outcomes of the first 100 donor-recipient cycles, using vitrified donated oocytes, and compare them to 91 fresh oocyte donation cycles (where the donors for the cryo bank were the same as for the fresh donations).DESIGN: Longitudinal observational study with retrospective data comparison.MATERIALS AND METHODS: 81 oocyte donors (mean age: 26.4+/-2.7) performed 92 donation cycles for the cryo bank and another 91 cycles of fresh donations during the period of May 2006 and March 2009. A total of 1988 M2 eggs were vitrified for the donor-bank using a DMSO/EG vitrification protocol. ICSI was performed 2-3 h after warming (vitrified eggs) or 3-4 h after egg retrieval (fresh donations). Embryo transfer was performed on day 5. Results were evaluated using Chi-square or One-way ANOVA tests at P<0.05 level.RESULTS: Mean ages of recipients were 40.9+/-4.9 and 41.2+/-4.7 (vitrified vs. fresh eggs respectively, NS). 604 out of 707 warmed oocytes survived the vitrification (85%) and were inseminated (mean 6.0 per patient); with fresh donation an average of 25.2 cumulus/egg complexes were used per patient (P<0.001). Fertilization rate was 76.5% and 56.8% in the vitrified/warmed vs. fresh donation groups respectively (P<0.01). Embryo developmental rates were similar on day 3 and day 5 in both groups. 2.08+/-0.54 and 1.97+/-0.51 embryos were transferred (NS) and 1.5+/-1.5 and 12.5+/-8.8 embryos were cryopreserved (P<0.0001) in the vitrified/warmed vs. fresh donation groups, respectively. Clinical pregnancy rate was 67% (67/100) and 69% (63/91; NS) and implantation rate was 52% (108/208) and 56% (100/179; NS) in the cryo vs. fresh donation groups, respectively.CONCLUSIONS: The results of the present study demonstrate that cryo banking of donated oocytes provides excellent laboratory and clinical outcomes, comparable in all aspects to fresh donation (using the same donors); however, it represents a more efficient and possibly safer alternative both to the patients and to the practitioners. OBJECTIVE: To evaluate laboratory and clinical outcomes of the first 100 donor-recipient cycles, using vitrified donated oocytes, and compare them to 91 fresh oocyte donation cycles (where the donors for the cryo bank were the same as for the fresh donations). DESIGN: Longitudinal observational study with retrospective data comparison. MATERIALS AND METHODS: 81 oocyte donors (mean age: 26.4+/-2.7) performed 92 donation cycles for the cryo bank and another 91 cycles of fresh donations during the period of May 2006 and March 2009. A total of 1988 M2 eggs were vitrified for the donor-bank using a DMSO/EG vitrification protocol. ICSI was performed 2-3 h after warming (vitrified eggs) or 3-4 h after egg retrieval (fresh donations). Embryo transfer was performed on day 5. Results were evaluated using Chi-square or One-way ANOVA tests at P<0.05 level. RESULTS: Mean ages of recipients were 40.9+/-4.9 and 41.2+/-4.7 (vitrified vs. fresh eggs respectively, NS). 604 out of 707 warmed oocytes survived the vitrification (85%) and were inseminated (mean 6.0 per patient); with fresh donation an average of 25.2 cumulus/egg complexes were used per patient (P<0.001). Fertilization rate was 76.5% and 56.8% in the vitrified/warmed vs. fresh donation groups respectively (P<0.01). Embryo developmental rates were similar on day 3 and day 5 in both groups. 2.08+/-0.54 and 1.97+/-0.51 embryos were transferred (NS) and 1.5+/-1.5 and 12.5+/-8.8 embryos were cryopreserved (P<0.0001) in the vitrified/warmed vs. fresh donation groups, respectively. Clinical pregnancy rate was 67% (67/100) and 69% (63/91; NS) and implantation rate was 52% (108/208) and 56% (100/179; NS) in the cryo vs. fresh donation groups, respectively. CONCLUSIONS: The results of the present study demonstrate that cryo banking of donated oocytes provides excellent laboratory and clinical outcomes, comparable in all aspects to fresh donation (using the same donors); however, it represents a more efficient and possibly safer alternative both to the patients and to the practitioners.

OBJECTIVE: Our objective was to investigate the efficiency of multiple sharing of cryopreserved sibling oocytes in comparison to fresh oocyte donation cycles.DESIGN: Prospective study.MATERIALS AND METHODS: Oocyte donations were divided into two groups: cryopreserved oocyte donation (vitrification) for multiple recipients (group A) and fresh oocyte donation for single recipient (group B). In group A, 59 recipients (40.7±5.1 yr) were matched to use donor eggs from the cryo-oocyte bank with 25 donors (27.0±2.6 yr) oocytes. In group B, 12 out of those 25 donors who had fresh oocyte donation before. In group A, there were 20 donors whose oocytes were shared with 2 recipients per donation, 2 donors whose oocytes were shared with 3 recipients, 2 donors whose oocytes were shared with 4 recipients, and 1 donor oocytes were shared with 5 recipients. Statistical evaluation of data was performed by the Chi-square or by the One-way ANOVA tests at the level of P<0.05.RESULTS: In group A, 356 out of the 418 vitrified/warmed oocytes from 25 donors (7.1±2.1; 85%) survived. Fertilization rate was 88.5% (A: 315/356) and 62.5 % (B: 135/216), respectively (P<0.05). Blastocyst rate was 72% (A: 226/315) and 76.3% (B: 103/135), respectively (NS). In group A, 125 embryos were transferred to 59 recipients (2.1±0.46); 41 out of 59 had a clinical pregnancy (66 FCAs detected; 53% IR). Twenty-five out of 40, 6 out of 6, 7 out of 8, and 3 out of 5 recipients became pregnant from donors split to 2, 3, 4 and 5 ways, respectively (NS). In group B, 24 embryos were transferred to 12 recipients (2.0±0); 7 out of 12 had a clinical pregnancy (11 FCAs detected; 46% IR) (NS).CONCLUSIONS: We have demonstrated that splitting the donor oocytes among several recipients was an effective practice by using oocyte cryo-banking, because the clinical outcomes were comparable to fresh donation cycles that use one donor for one recipient. The multiple sharing of cryo-banked oocytes may become a successful alternative for the treatment of women requiring donated eggs. OBJECTIVE: Our objective was to investigate the efficiency of multiple sharing of cryopreserved sibling oocytes in comparison to fresh oocyte donation cycles. DESIGN: Prospective study. MATERIALS AND METHODS: Oocyte donations were divided into two groups: cryopreserved oocyte donation (vitrification) for multiple recipients (group A) and fresh oocyte donation for single recipient (group B). In group A, 59 recipients (40.7±5.1 yr) were matched to use donor eggs from the cryo-oocyte bank with 25 donors (27.0±2.6 yr) oocytes. In group B, 12 out of those 25 donors who had fresh oocyte donation before. In group A, there were 20 donors whose oocytes were shared with 2 recipients per donation, 2 donors whose oocytes were shared with 3 recipients, 2 donors whose oocytes were shared with 4 recipients, and 1 donor oocytes were shared with 5 recipients. Statistical evaluation of data was performed by the Chi-square or by the One-way ANOVA tests at the level of P<0.05. RESULTS: In group A, 356 out of the 418 vitrified/warmed oocytes from 25 donors (7.1±2.1; 85%) survived. Fertilization rate was 88.5% (A: 315/356) and 62.5 % (B: 135/216), respectively (P<0.05). Blastocyst rate was 72% (A: 226/315) and 76.3% (B: 103/135), respectively (NS). In group A, 125 embryos were transferred to 59 recipients (2.1±0.46); 41 out of 59 had a clinical pregnancy (66 FCAs detected; 53% IR). Twenty-five out of 40, 6 out of 6, 7 out of 8, and 3 out of 5 recipients became pregnant from donors split to 2, 3, 4 and 5 ways, respectively (NS). In group B, 24 embryos were transferred to 12 recipients (2.0±0); 7 out of 12 had a clinical pregnancy (11 FCAs detected; 46% IR) (NS). CONCLUSIONS: We have demonstrated that splitting the donor oocytes among several recipients was an effective practice by using oocyte cryo-banking, because the clinical outcomes were comparable to fresh donation cycles that use one donor for one recipient. The multiple sharing of cryo-banked oocytes may become a successful alternative for the treatment of women requiring donated eggs.

OBJECTIVE: Dimethyl sulfoxide (DMSO) has been widely used as a cryoprotectant for oocyte cryopreservation. However, it has been demonstrated that DMSO could potentially trigger oocyte activation. Thus, our objective was to compare oocyte vitrification outcomes with vitrification solution containing DMSO vs. without DMSO. DESIGN: Prospective study. MATERIALS AND METHODS: Twenty-eight recipients with an average age of 41.5±5.5 yr were matched to use donor eggs from the egg bank (16 donors: average age of 26.9±2.5 yr). Cryopreservation on donor sibling oocytes was performed by two methods: cryoprotectants containing 15% ethylene glycol, 15% DMSO and 0.5 M sucrose (group A) and cryoprotectants containing 30% ethylene glycol and 0.5 M sucrose (group B). Sibling oocytes from both groups were warmed for each recipient. Oocytes were fertilized by ICSI 2-3 hours after warming. On day 5, blastocyst formation was assessed and embryo transfer was performed. Results were analyzed by the Chi-square (P<0.05) test. RESULTS: A total of 196 MII oocytes were warmed for 28 recipients (7.0±2.35). One hundred twenty-six oocytes were warmed from group A (4.5±1.75), and 70 oocytes were warmed from group B (2.5±0.83). Survival rates were 90% (113/126) and 94% (66/70; NS) in A and B, respectively. Fertilization rates were 82% (103/126) in A, and 83% (58/70; NS) in B. Blastocyst formation rates were 65% (82/126) and 57% (40/70; NS) in A and B. Embryos for transfer were selected from group A (35) and B (21); 56 blastocysts were transferred to 28 recipients (2.0±0.38); 18 out of 28 had positive hCG (64%). Thirteen recipients had a clinical pregnancy (22 FCAs detected; 39% implantation rate), and all 13 pregnancies are ongoing. CONCLUSIONS: We demonstrated that the survival, fertilization, and blastocyst rates were similar when use sibling oocytes to compare vitrification solution with and without DMSO. It suggests a cryoprotectant solution without DMSO can provide equivalent efficiency of oocyte vitrification to a common protocol that contains DMSO.

OBJECTIVE: Cryopreserved embryos after slow-freezing are shipped routinely by dry shippers among ART laboratories without affecting their survival rates. However, little information is known about whether the vitrified oocytes/embryos can be maintained in the condition of dry shipper. We aimed to investigate if exposing vitrified oocytes to conditions in a dry shipper used for transportation would impact survival rates.DESIGN: Prospective study.MATERIALS AND METHODS: A total of 163 in-vivo matured MII oocytes from seven donors were cryopreserved on the day of oocyte retrieval and stored in liquid nitrogen dewars as a control group (A). Cryopreservation of oocytes was performed by vitrification using 15% ethylene glycol, 15% DMSO and 0.5 M sucrose with cryotop. The other 70 immature oocytes from the same donors were cultured up to 28 h, and 49 of them were in vitro matured (IVM) and vitrified on the following day of oocyte retrieval. The vitrified IVM oocytes were transferred and held in the dry shipper (MVE sc4/2v) for 60 h as a treatment group (B). Oocyte warming (in both control and treatment groups) was performed by serial dilutions in three steps using 1.0M, 0.5M, and 0M sucrose solutions. Results were analyzed by the Chi-square (P<0.05) test.RESULTS: In group A, a total of 54 oocytes were warmed, and 47 out of 54 survived (87.0%). In group B, 42 out of 49 oocytes survived after vitrification, exposure to vapor phase in dry shipper, and warming (85.7%; NS).CONCLUSIONS: In the present study, we have shown that survival rate of vitrified oocytes was not affected after exposure to the environment of the dry shipper. These results suggest that oocytes cryopreserved by the vitrification technique may be shipped safely using the dry shipper. As an increasing number of IVF clinics are switching from slow-freezing to the vitrification method to cryopreserve oocytes and embryos, the results of this study provide critical information that ensures vitrified oocytes/embryos can be transported in the dry shipper safely. OBJECTIVE: Cryopreserved embryos after slow-freezing are shipped routinely by dry shippers among ART laboratories without affecting their survival rates. However, little information is known about whether the vitrified oocytes/embryos can be maintained in the condition of dry shipper. We aimed to investigate if exposing vitrified oocytes to conditions in a dry shipper used for transportation would impact survival rates. DESIGN: Prospective study. MATERIALS AND METHODS: A total of 163 in-vivo matured MII oocytes from seven donors were cryopreserved on the day of oocyte retrieval and stored in liquid nitrogen dewars as a control group (A). Cryopreservation of oocytes was performed by vitrification using 15% ethylene glycol, 15% DMSO and 0.5 M sucrose with cryotop. The other 70 immature oocytes from the same donors were cultured up to 28 h, and 49 of them were in vitro matured (IVM) and vitrified on the following day of oocyte retrieval. The vitrified IVM oocytes were transferred and held in the dry shipper (MVE sc4/2v) for 60 h as a treatment group (B). Oocyte warming (in both control and treatment groups) was performed by serial dilutions in three steps using 1.0M, 0.5M, and 0M sucrose solutions. Results were analyzed by the Chi-square (P<0.05) test. RESULTS: In group A, a total of 54 oocytes were warmed, and 47 out of 54 survived (87.0%). In group B, 42 out of 49 oocytes survived after vitrification, exposure to vapor phase in dry shipper, and warming (85.7%; NS). CONCLUSIONS: In the present study, we have shown that survival rate of vitrified oocytes was not affected after exposure to the environment of the dry shipper. These results suggest that oocytes cryopreserved by the vitrification technique may be shipped safely using the dry shipper. As an increasing number of IVF clinics are switching from slow-freezing to the vitrification method to cryopreserve oocytes and embryos, the results of this study provide critical information that ensures vitrified oocytes/embryos can be transported in the dry shipper safely.

OBJECTIVE: The ability to efficiently cryopreserve oocytes can serve for various fertility treatments related applications. The aim of this study is to evaluate the applications and results of oocyte cryopreservation in our ART program. DESIGN: Retrospective study. MATERIALS AND METHODS: From May 2006 to April 2009, we have identified 5 distinct egg freezing applications: Group 1 "Rescue" egg cryo cycles when sperm has not been available at egg retrieval, Group 2 Fertility Preservation for single women, Group 3 an elective alternative to embryo freezing when there are ethical concerns with embryo cryopreservation, Group 4 Egg donation program to enhance management of donors and recipients and Group 5 Cancer patients before radio and or chemotherapy. RESULTS: In group 5 there were 14 women (age average 24 ± 4 years old) who have had frozen 220 oocytes (average per patient 14 ± 10) None of those oocytes have been warmed yet. Results are summarized in Table 1.Table 1Efficiency of different applications of oocyte freezing.Groups1234# of Patients82738107Age Avg (+/-SD)33.9 (5.1)35.5 (4.4)33.7 (4.3)26.1 (2.8)# Eggs Avg (mean)105 (13.1)272 (9.7)469 (12.3)2090 (22)# of Patients with Thaw325111Recipient Age avg (+/-SD)34.0 (5.6)35.5 (0.5)34.6 (3.5)41.0 (4.9)# Eggs thawed (mean)37 (12.3)19 (9.5)55 (11)781 (7.0)Survival rate %78846986Fertilization rate %76758289Blastocyst rate %32507469Clinical pregnancy rate %67508065Implantation rate %26173850 Open table in a new tab CONCLUSIONS: The excellent survival, fertilization, blastocyst and pregnancy/implantation rates obtained after egg warming in the different groups demonstrates the high efficiency of oocyte cryo banking when used in combination with a competent vitrification method. These results demonstrate a clear clinical benefit for patients with different medical needs/indications that now can be managed through egg cryopreservation as an advanced treatment option for assisted reproduction.

OBJECTIVE: To evaluate the efficiency of a new vitrification carrier (Cryolock®) by analyzing clinical outcomes, after warming and embryo transfer (ET) of vitrified blastocysts, derived from previously vitrified/warmed oocyte cycles from the donor egg bank. DESIGN: Observational study. MATERIALS AND METHODS: A total of 15 recipients (who were not pregnant after the initial oocyte warming treatment cycle) have had frozen embryo replacement on day 20 of a supplemented cycle (embryos originating from vitrified/warmed oocytes were cryopreserved at the blastocyst stage using Cryolock® (Biodiseño Ltda, Bogota-Colombia) as a carrier device); Blastocyst warming was performed by serial dilutions in three steps using 1.0M, 0.5M, and 0M sucrose solutions. Embryo transfer was performed 2-3 h after warming. HCG level was tested 10 days after ET, clinical pregnancy was confirmed by detecting fetal cardiac activity on the 7th week of pregnancy. RESULTS: Blastocyst survival rate after warming was 95% (38/40), 36 embryos were transferred (average 2.4 per transfer), Twelve clinical pregnancies were obtained (80%), 19 embryos implanted (53%). Two first trimester miscarriages have occurred, and seven pregnancies are currently ongoing and 3 deliveries were obtained by date (with 5 healthy babies - 3 females and 2 males, no abnormalities detected). CONCLUSIONS: These results show that the Cryolock® device is a suitable carrier for embryo (re-) vitrification. Additionally, the pregnancy outcomes demonstrate that oocyte vitrification and embryo re-vitrification is an efficient technical and treatment approach, not impacting oocyte/embryo viability in a significant manner. High survival and implantation rates of the (double) cryopreserved embryos suggest that viability of oocyte and blastocyst is retained when using the combination of Cryolock® and vitrification technique.