Clinical outcome of treatment cycles using preimplantation genetic diagnosis for structural chromosomal abnormalities

OBJECTIVES: To explore oocyte recovery, embryo quality, the number of transferable embryos and pregnancy rate after preimplantation genetic diagnosis (PGD) in patients with structural chromosomal aberrations. METHODS: PGD was performed in seven couples with Robertsonian translocations (Rob), eight couples with reciprocal translocations (Rec), two couples with inversions and one couple with a deletion. A total of 43 treatment cycles were carried out. RESULTS: A total of 14.2 oocytes per cycle were retrieved. Fertilisation and cleavage rates were 63% and 58%, respectively. Of the biopsied embryos 20% were transferable. Comparison of the Rob and Rec group revealed no significant differences in number of oocytes, fertilisation or cleavage rates. The number of transferable embryos after biopsy was significantly higher in the Rob group than in the Rec group. When embryo transfer (ET) was performed the pregnancy rate did not differ between the Rob and the Rec groups. Twenty-eight embryo transfers (one or two embryos) were carried out leading to eight clinical pregnancies (29% per ET): two twins, four singletons, one miscarriage and one ectopic pregnancy. All the children are carriers of balanced chromosomal aberrations. CONCLUSION: An acceptable pregnancy rate can be achieved among couples with structural chromosomal abnormalities.     

Efficacy and clinical outcome of preimplantation genetic diagnosis using FISH for couples of reciprocal and Robertsonian translocations: the Korean experience

OBJECTIVE: To evaluate the efficacy and clinical outcome of preimplantation genetic diagnosis (PGD) using fluorescence in situ hybridization (FISH) for couples with chromosomal translocations. METHODS: PGD using FISH was performed in 59 cycles of 43 couples with reciprocal translocations, and 11 cycles of 6 couples with Robertsonian translocations. The diagnostic and clinical data were reviewed in a series of 70 treatment cycles of 49 couples from January 2001 to June 2002 at Samsung Cheil Hospital, Korea. RESULTS: A total of 1408 oocytes were retrieved, and 938 (81.7%) out of 1148 matured oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Single blastomere biopsy and FISH analysis were successfully carried out in 99.3% (890/896) and 94.4% (840/890), respectively. Among 193 normal or balanced embryos, 169 embryos were transferred in 64 cycles (91.4% per started cycle). Twenty clinical pregnancies including two ectopic pregnancies and three spontaneous miscarriages (28.6% per started cycle, 31.3% per transfer cycle, 40.8% per couple) were established. Of the three spontaneous miscarriages, one was karyotyped as normal, one had an unbalanced arrangement and one was tetraploid. One case of preterm twin delivery occurred and 16 healthy babies were delivered in 12 single and 2 twin pregnancies. CONCLUSION: The clinical outcome was successful in 28.6% (14/49) of the treated couples with translocations after PGD. The spontaneous abortion rate was significantly reduced from 95.8% (69/72) to 16.7% (3/18) in these couples.     

Cumulative pregnancy rates after transfer of fresh and thawed embryos

Frozen-thawed embryo transfer is an effective procedure that allows further possibilities of pregnancy in addition to those obtained after the fresh in vitro fertilization (IVF). In our follow-up study we analysed all fresh embryo transfer procedures and every frozen-thawed embryo transfer performed from January 2000 to December 2001 evaluating the cumulative pregnancy rates. The study population was divided into two groups according to the female age: <38 years (group I) and >38 years (group II). All the best embryos were chosen for transfer and all the supernumerary good quality embryos were cryopreserved on the day of transfer. The embryos were then thawed and manipulated using a new technique. In group I, 527 patients (619 cycles) underwent fresh embryo transfer and in 232 of them (238 cycles) the embryos were frozen (44% per patients and 38.4% per cycle). In group II, 156 patients (193 cycles) underwent fresh embryo transfer and in 14 of them (15 cycles) the embryos were frozen (9% per patient and 7.8% per cycle). The pregnancy rate of group I patients that had their supernumerary embryos frozen (232 patients and 238 cycles) was 47.4% per cycle and 48.7% per patient whereas in the same population of group II patients (14 patients and 15 cycles) the clinical pregnancy rate was 35.7% per cycle and 38.5% per patients. The cumulative clinical pregnancy rate after transfer of fresh and thawed embryos was: group I, 74% per cycle and 76% per patients; group II, 42.8% per cycle and 46.1% per patient. Frozen-thawed embryo transfer is a cost-effective practice.     

Preimplantation genetic diagnosis significantly improves the pregnancy outcome of translocation carriers with a history of recurrent miscarriage and unsuccessful pregnancies

Preimplantation genetic diagnosis (PGD) for translocations has been shown to significantly reduce the risk of recurrent miscarriage, but because the majority of embryos produced are unbalanced, pregnancy rate is relatively low since 20% or more cycles have no normal or balanced embryos to transfer. The purpose of this study was to evaluate whether PGD could improve pregnancy outcome in translocation carriers with a history of two or more consecutive miscarriages and no live births. PGD for translocations was offered to translocation carriers with two or more previous miscarriages (average 3.5) and no live births (0/117 pregnancies) using a combination of distal and proximal probes to the breakpoints. After PGD, only 18.3% of embryos were normal or balanced. Only 5.3% of pregnancies were lost after PGD compared with 100% before PGD (P < 0.001). The cumulative pregnancy rate was 57.6% and the cumulative ongoing pregnancy rate was 54.5% in the short period of time of 1.24 IVF cycles, or 46.3% and 43.9% respectively per cycle. In conclusion, PGD significantly reduced losses and increased the number of viable pregnancies (P < 0.001). IVF plus PGD are a faster method of conceiving a live child than natural conception, at least for translocation carriers with recurrent miscarriages and no previous live births.     

Current features of preimplantation genetic diagnosis

More than 4000 preimplantation genetic diagnosis (PGD) cycles have been performed, suggesting that PGD may no longer be considered a research activity. The important present feature of PGD is its expansion to a variety of conditions, which have never been considered as an indication for prenatal diagnosis, including the late-onset disorders with genetic predisposition and preimplantation non-disease testing, with the further improvement of the accuracy of PGD for single gene disorders. PGD has also become a useful tool for the improvement of the effectiveness of IVF, through avoiding the transfer of chromosomally abnormal embryos, representing more than half of the embryos routinely transferred in IVF patients of advanced maternal age and other poor prognosis patients. PGD is of particular hope for the carriers of balanced chromosomal translocations, as it allows accurate pre-selection of a few balanced or normal embryos resulting from the extremely poor meiotic outcome, especially in reciprocal translocations. With the current progress in polymerase chain reaction- (PCR-) based detection of chromosomal abnormalities in oocytes and embryos, PGD may soon be performed for both chromosomal and single gene disorders using the same biopsied polar body or blastomere, frequently required with the currently expanded PGD application. The available clinical outcome data of more than 3000 PGD embryo transfers further suggest an acceptable pregnancy rate and safety of the procedure, as demonstrated by the follow-up information available for more than 500 children born from these PGD transfers.     

玻璃化冷冻法冻融经植入前遗传学诊断后囊胚的应用初探

目的:探讨玻璃化冷冻技术冻融经卵裂球活检后囊胚的可行性。方法:将活检后剩余的可移植囊胚用玻璃化冷冻保存,并在冷冻前人工皱缩囊胚腔,在需要移植时予以解冻囊胚进行移植。结果:24例共进行24个活检周期,活检了159个胚胎,活检后胚胎囊胚形成率60.38%(96/159)。有17个周期共移植26枚新鲜可用囊胚,成功种植13个(50.0%),11例获得临床妊娠(64.71%),7个周期因无可移植胚胎或卵巢过度刺激等因素而取消移植。10例患者(10个周期)有30个可移植囊胚进行了玻璃化冷冻保存,其中6例患者因未成功生育要求解冻其囊胚进行移植。共解冻8枚囊胚,全部存活并移植,5例获单胎妊娠;2例已分娩正常婴儿,3例继续妊娠中。结论:玻璃化冷冻技术结合人工皱缩囊胚腔能冷冻保存经卵裂球活检后的囊胚。     

Preimplantation genetic diagnosis by fluorescence in situ hybridization of reciprocal and Robertsonian translocations

ObjectiveThe presence of reciprocal and Robertsonian chromosomal rearrangement is often related to recurrent miscarriage. Using preimplantation genetic diagnosis, the abortion rate can be decreased. Cases treated at our center were reviewed.Materials and methodsA retrospective analysis for either Robertsonian or reciprocal translocations was performed on all completed cycles of preimplantation genetic diagnosis at our center since the first reported case in 2004 until the end of 2010. Day 3 embryo biopsies were carried out, and the biopsied cell was checked by fluorescent in situ hybridization using relevant informative probes. Embryos with a normal or balanced translocation karyotype were transferred on Day 4.ResultsThirty-eight preimplantation genetic diagnosis cycles involving 17 couples were completed. A total of 450 (82.6%) of the total oocytes were MII oocytes, and 158 (60.0%) of the two-pronuclei embryos were biopsied. In 41.4% of the fluorescent in situ hybridization analyses, the results were either normal or balanced. Embryos were transferred back after 21 cycles. Three babies were born from Robertsonian translocation carriers and another two from reciprocal translocation carriers. The miscarriage rate was 0%. Among the reciprocal translocation group, the live delivery rate was 8.3% per ovum pick-up cycle and 18.2% per embryo transfer cycle. Among the Robertsonian translocation group, the live delivery rate was 14.3% per ovum pick-up cycle and 20.0% per embryo transfer cycle.ConclusionThere is a trend whereby the outcome for Robertsonian translocation group carriers is better than that for reciprocal translocation group carriers. Aneuploidy screening may possibly be added in order to improve the outcome, especially for individuals with an advanced maternal age. The emergence of an array-based technology should help improve this type of analysis.     

Gestational carrier is an optimal method for pregnancy in patients with vaginal agenesis (Rokitansky syndrome)

OBJECTIVE: To evaluate the results of successful pregnancy for patients with Mayer-Rokitansky-Kuster-Hauser syndrome using a gestational carrier. METHODS: All gestational carrier patients who attended our infertility clinic between 1995 and 2002 were reviewed for this study. Of the patients, 6 women with MRKH syndrome had 12 ovarian stimulation cycles, which resulted in 12 fresh and 5 frozen embryo transfers into six gestational carriers. RESULTS: The mean number (+/-SD) of embryos obtained per cycle was 4.8 (+/-2.9). Either two (n = 15) or three (n = 2) embryos were transferred to the gestational carrier. Three pregnancies were achieved following fresh embryo transfer, which included one clinical pregnancy that ended in spontaneous abortion, a singleton, and a set of twins. The pregnancy rate for fresh embryo transfer was 25% per retrieval and 50% per patient. No pregnancy was achieved following frozen embryo transfer. CONCLUSION: Gestational carrier is shown to be an effective treatment for patients with Mayer-Rokitansky-Kuster-Hauser syndrome.     

Pregnancies from single normal embryo transfer in women older than 40 years

The aim of this retrospective study was to determine the pregnancy rate from the transfer of single genetically normal embryos in patients of advanced reproductive age. The study group included 23 patients (mean age 42.2 +/- 1.3 years) who underwent 27 in-vitro fertilization (IVF) cycles in which preimplantation genetic diagnosis (PGD) was carried out on single blastomeres from day 3 embryos. The control group included 54 patients (mean age 43.3 +/-1.9 years) who underwent 69 cycles of IVF without PGD. Ovarian stimulation in all patients consisted of follicular phase leuprolide acetate administration, followed by ovulation induction with gonadotrophins. The mean number of biopsied embryos was 5.6 +/- 0.5. No embryo transfer occurred in six patients (10 cycles) because all embryos biopsied were abnormal. Seventeen patients (17 cycles) each had one genetically normal embryo transferred resulting in six on-going clinical pregnancies (35% per embryo transfer cycle). The mean number of embryos transferred in the control group was 4.0 +/- 0.8. Nineteen clinical pregnancies were obtained in 69 transfer cycles in the control group (28% per embryo transfer cycle). The transfer of a single normal embryo in patients of advanced reproductive age can lead to acceptable pregnancy rates. Aneuploidy appears to be a major cause of reproductive failure in this group of patients.     

未经促排卵的未成熟卵母细胞行体外成熟治疗不孕症的临床研究

目的探讨未经任何药物刺激的未成熟卵母细胞行体外成熟（IVM）治疗不孕症的临床价值。方法40例不孕患者接受54个IVM周期,其中多囊卵巢综合征（PCOS）不孕患者26例,经其他辅助生育技术失败14例。在未采用任何药物刺激的前提下,于月经周期的第9—12天,在超声引导下经阴道对两侧卵巢内直径≤10mm的卵泡进行穿刺取卵。对取出卵母细胞于体外培养24～48h,待第一极体出现后,进行卵母细胞质内单精于注射（ICSI）,18h后观察受精情况,继续培养24—48h,直至胚胎移植,移植前行激光辅助胚胎孵化。结果54个IVM周期中,有7个周期取消,取消率为13％;共移植周期47个,共获得未成熟卵母细胞857个,平均每周期18．2个。体外培养48h后,卵母细胞成熟率为73．7％（632／857）,正常受精率为75．3％（476／632）,卵裂率为91．2％（434／476）。移植日子宫内膜厚度平均为8．9mm,平均移植胚胎4．3个（2—6个）;1例生化妊娠,19例临床妊娠,每取卵周期的临床妊娠率为35％（19／54）,每移植周期的临床妊娠率为40％（19／47）。26例PCOS不孕患者共移植周期34个,1例生化妊娠,15例临床妊娠,每移植周期的临床妊娠率为44％（15／34）。结论未经促排卵药物刺激的卵母细胞行IVM用于治疗各种原因的不孕症,尤其是PCOS不孕患者,是一种有效的治疗方法。     

Blastocyst-stage transfer of poor-quality cleavage-stage embryos results in higher implantation rates

OBJECTIVE: To determine the feasibility and success of blastocyst-stage embryo transfers in patients having only fair and poor quality cleavage-stage embryos on day 3. DESIGN: Prospective case study with historic controls. SETTING: Tertiary care private hospital IVF center. PATIENT(S): A total of 158 day 5 embryo transfer cycles in patients with grade 3 and grade 4 cleavage-stage embryos. Control group consisted of 162 day 3 transfer cycles performed with embryos of similar quality. INTERVENTION(S): In vitro culture of embryos up to the blastocyst stage. MAIN OUTCOME MEASURE(S): The percentage of cycles that culminated in the transfer of at least one blastocyst and implantation and pregnancy rate related to the day of transfer. RESULT(S): In the day 3 transfer group, a mean of 5.2 embryos were replaced per patient. This was significantly more than the mean of 2.4 embryos that could be replaced on day 5 (P <.001). The clinical pregnancy rate per embryo transfer was 27.2% and 33.5% in the two groups, respectively (P >.05). The implantation rate per embryo was significantly higher in the day 5 transfer group (15% vs. 5.9%). The multiple pregnancy and abortion rates were similar between the groups. CONCLUSION(S): Transfer of fair and poor quality embryos at the blastocyst stage is feasible and is associated with higher implantation rates as compared to transfer of similar quality embryos on day 3.     

Embryo development characteristics in Robertsonian and reciprocal translocations: a comparison of results with non-translocation cases

The effect of translocations on embryo development was evaluated and results were compared in terms of embryo development with those of embryos obtained from standard intracytoplasmic sperm injection (ICSI) cycles. In 23 translocation carriers with 34 cycles, fertilization, pronuclear morphology scoring (PMS), developmental arrest, cleavage and blastocyst formation were evaluated and compared with embryos obtained from non-translocation cases undergoing ICSI (n = 98 cycles). In 28 cycles, preimplantation genetic diagnosis (PGD) was performed on prezygotes (first and second polar body biopsy for female carriers; n = 3) or on embryos having seven or more blastomeres (blastomere biopsy; n = 25). In six cycles for four couples, probes for translocated chromosomes were not available, so PGD could not be performed. Overall, in translocation cases, a lower fertilization rate, a higher rate of retarded embryo development, and a lower rate of blastocyst formation were observed compared with embryos of non-translocation cases. Fluorescence in-situ hybridization (FISH) analysis showed a 70.9% abnormality rate for reciprocal translocations and 55.0% for Robertsonian translocations respectively. In cases with Robertsonian and reciprocal translocation carriers, the probability of poor embryo development, which may be a result of high segregation abnormalities, may negatively affect the outcome of assisted reproductive techniques. This poor prognosis should also be considered when genetic counselling for translocation is given.     

A flexible protocol for cryopreservation of pronuclear and cleavage stage embryos created by conventional in vitro fertilization and intracytoplasmic sperm injection

OBJECTIVES: To evaluate the hospital's cryopreservation protocol. STUDY DESIGN: A retrospective cohort analysis of 30 conventional IVF and 44 ICSI cycles in an assisted conception unit at a tertiary referral hospital. All supernumerary embryos were cryopreserved at the pronuclear or blastomere stage. The survival, morphology, implantation and pregnancy rates were evaluated. The chi2 test and Fisher's exact test were used to determine the statistical significance. RESULTS: A total of 327 pronuclear and cleavage stage embryos were cryopreserved. The post thaw survival rates of 107 conventional IVF and 220 ICSI embryos were 90.6% and 69.0%, respectively. Of the thawed cleavage stage embryos from 43 IVF and 88 ICSI cycles, 90.6% and 69.3% were intact, respectively. Of the thawed pronuclear stage embryos from 64 IVF and 132 ICSI cycles, 90.6% and 68.9% were intact with cleavage rates of 57.8% and 56%, respectively. In the final 27 conventional IVF and 41 ICSI frozen-thawed embryo transfer cycles, the pregnancy rates were 18.5% and 19.5%, respectively. CONCLUSIONS: The adopted cryopreservation protocol flexibly allows for the selection of cleavage-stage embryos for fresh embryo transfer and the cryopreservation of all supernumerary embryos at the pronuclear or the cleavage stage in a single cycle with satisfactory pregnancy rates. Further validation of this protocol is required.     

冻融胚胎移植周期中胚胎因素的分析研究

目的:分析冻融胚胎移植周期中胚胎卵裂球损伤程度与有丝分裂的恢复对于临床结局的影响。方法:171例患者共进行冻融胚胎移植206个周期,采用慢速冷冻法冻存d3胚胎,快速解冻法复苏后继续培养4h后移植,根据复苏后卵裂球的损伤程度分为完整组、混合组和损伤组,另根据复苏后4h胚胎进行分裂的情况分为分裂组,混合组和未分裂组,比较各组间的临床妊娠率和单胚着床率。结果:206个周期共复苏胚胎632枚,复苏存活率85.44%(540/632),移植胚胎508个,周期妊娠率36.41%(75/206),单胚着床率19.88%(101/508),完整组与损伤组间、分裂组与未分裂组间的临床妊娠率和单胚着床率都有显著性差异(P<0.05)。结论:冻融胚胎移植周期中胚胎卵裂球的损伤程度与有丝分裂的恢复是影响临床结局的重要因素。     

Predictability of preimplantation genetic diagnosis of aneuploidy and translocations on prospective attempts

The aim of this study was to determine if the outcomes of aneuploidy and translocation testing by preimplantation genetic diagnosis (PGD) at the 8-cell stage have a predictive value for new genetic diagnosis cycles. In total, 83 cycles (39 patients) undergoing PGD of translocations and 378 cycles (176 patients) of aneuploidy were included. Predictability, defined as having similar rate (+/-20%) of euploid embryos in the first and successive cycles, was found in 66% of patients undergoing aneuploidy testing. Predictability was found significantly more often in patients undergoing PGD of translocations (90%, P = 0.006). In addition, patients with 0, <30 or > or =30% euploid embryos in the first cycle were compared and groups 0 and <30% had significantly fewer euploid embryos in the second cycle (22-26%) than those of the group with > or =30% (37%) (P < 0.05). Patients who did not become pregnant after the first attempt were stimulated more aggressively than those becoming pregnant, producing significantly more embryos in the second than in the first cycle (P < 0.001). Therefore, correlation between euploidy rate and pregnancy rate could not be assessed objectively between cycles. In conclusion, the PGD results of a first cycle can predict the results of the second cycle, but this is likely to be of more value when the condition investigated is translocation rather than aneuploidy. The chance of pregnancy is usually related to the number of euploid embryos.     

Three hundred and thirty cycles of preimplantation genetic diagnosis for serious genetic disease: clinical considerations affecting outcome

OBJECTIVE: To report on our experience with preimplantation genetic diagnosis (PGD) cycles performed for serious genetic disease in relation to the clinical factors affecting outcome. DESIGN: Retrospective review of data from a single centre. SETTING: Tertiary referral PGD centre in a London teaching hospital. METHODS: The PGD cycles included 172 cycles for chromosome rearrangements, 96 cycles for single-gene disorders and 62 cycles for X-linked disorders. In vitro fertilisation was the preferred method in chromosome rearrangement and X-linked cases, while intra cytoplasmic sperm injection was used in all single-gene disorders. Appropriate in situ hybridisation fluorescence probes were used in chromosome rearrangement and X-linked cases and polymerase chain reaction was used in single-gene disorders. All pregnancies were followed till delivery. MAIN OUTCOME MEASURE: Live birth rate per PGD cycle started. RESULTS: Eighty-six percent of cycles started (283) reached oocyte retrieval and 3743 eggs were collected, of which 2086 fertilised normally (55.7%). Two hundred and fifty cycles (76%) had embryos sutiable for biopsy on day 3 of in vitro culture, 1714 embryos were biopsied, and in 205 cycles (62%), there was at least one unaffected embryo available for transfer, resulting in 90 pregnancies, 68 clinical pregnancies and 58 live birth. The live birth rate was 18% per cycle started, 21% per egg retrieval and 28% per embryo transfer which significantly affected the live birth outcome. Woman age, number of eggs collected and achieving cryopreservation of surplus embryos had no statistically significant effect on treatment outcome. CONCLUSIONS: The live birth outcome of PGD cycles for serious genetic disorder is modest and is affected by the number of embryos genetically suitable for transfer.     

ICSI outcome in patients of 40 years age and over: a retrospective analysis

OBJECTIVE: To report and analyse our experience with ICSI treatment in infertile women >/=40 years of age, with the intention of contributing to current debates on the effect of aging on the reproductive potential. STUDY DESIGN: 107 infertile couples in which the female partner was aged >/=40 years and who received ICSI treatment between January 1996 and December 1998. RESULTS: A total of 107 women underwent 171 treatment cycles during this period. Of 171 cycles initiated 33 were cancelled (cancellation rate=19.3%). In this way, 17 women did not have embryo transfer at all, while 90 patients had 138 cycles with oocyte retrieval and successful embryo transfer, with a mean number of embryos per transfer 2.36. Sixteen pregnancies occurred and eight of them ended in spontaneous abortion. The implantation rate was 4.9%, the pregnancy rate per initiated cycle was 9.35% and per transfer cycle 11.59%. The miscarriage rate was 50%. Moreover, 12 patients had supernumerary embryos, that were cryopreserved and transferred in 17 thawing cycles and resulted in two pregnancies ending in abortion. All pregnancies occurred when three embryos were available, except in two cases with two available embryos. The great majority of the total pregnancies (16 of 18) resulting in women aged between 40 and 42 years. CONCLUSION: Our data show that women 40 and older with existing ovarian function may benefit from ICSI treatment, even when the indication for treatment is male factor infertility. Supernumerary embryos, that are cryopreserved and transferred in subsequent cycles can improve the overall pregnancy rates per oocyte retrieval, although these women should be aware of the very high risk of miscarriage.     

Preimplantation diagnosis for aneuploidies in patients undergoing in vitro fertilization with a poor prognosis: identification of the categories for which it should be proposed

OBJECTIVE: To verify whether advantages can derive from the implementation of preimplantation genetic diagnosis for aneuploidy in patients with a poor prognosis of full-term pregnancy, compared with conventional treatment procedures. DESIGN: A randomized, controlled study. SETTING: Reproductive Medicine Unit of the Società Italiana Studi Medicina della Riproduzione, Bologna, Italy. PATIENT(S): In a total of 262 stimulated cycles, women presented with the following poor-prognosis indications: maternal age of > or =36 years (n = 157), > or =3 previous IVF failures (n = 54), and an altered karyotype (n = 51). After giving consent, 127 patients underwent preimplantation genetic diagnosis for aneuploidy, whereas 135 controls underwent assisted zona hatching. INTERVENTION(S): Analysis of chromosomes XY, 13, 14, 15, 16, 18, 21, and 22 was carried out with the fluorescence in situ hybridization technique in a blastomere biopsied from day 3 embryos. Assisted zona hatching was performed on day 3 embryos from the control group. MAIN OUTCOME MEASURE(S): Embryo morphology and chromosomal status, number of transferred embryos, clinical pregnancies, implantation rates, and abortions. RESULT(S): In the study group, 717 embryos were analyzed by fluorescence in situ hybridization, and 60% were chromosomally abnormal. A mean of 2.3+/-0.9 euploid embryos were transferred in 99 cycles, resulting in 37 clinical pregnancies (37%) and a 22.5% ongoing implantation rate. In the control group, 126 cycles were performed with 3.2+/-1.3 embryos transferred, yielding 34 clinical pregnancies (27%) and a 10.2% ongoing implantation rate. CONCLUSION(S): The advantage of selecting embryos with a normal chromosome complement has an immediate impact on the ongoing implantation rate, especially in patients aged > or =38 years and carriers of an altered karyotype.     

冷冻前胚胎因素对冻融胚胎移植结局的影响

目的:探讨冻融胚胎移植周期中冷冻前胚胎因素对临床结局的影响。方法:回顾分析本生殖中心2009年1月～9月的589个冻融胚胎移植周期,根据冷冻前受精方式、胚胎培养时间、胚胎卵裂球数目、冷冻前≥6细胞胚胎个数分组。结果:589例冻融移植周期中共解冻胚胎2185枚,复苏率为69.5%,临床妊娠率26.5%。不同受精方式的临床妊娠率分别为23.4%,33.2%,差异有统计学意义;D2胚胎和D3胚胎冷冻后复苏率和临床妊娠率差异有统计学意义(71.4%vs69.1%和20.2%vs30.1%);冷冻前胚胎≥6细胞和6细胞,两组的临床妊娠率(31.8%,22.0%)和卵裂球完全存活复苏率(23.7%,45.4%)比较,差异均有统计学意义;冷冻前3个及以上≥6细胞的胚胎复苏率最高为56.0%、卵裂球完全存活复苏率最低为20.9%,与冷冻前少于3个胚胎组相比差异有统计学意义。若冷冻前仅余1个≥6细胞胚胎,冷冻后复苏率显著高于仅余1个6细胞胚胎,但卵裂球完全存活复苏率显著降低;和仅余2个胚胎相比,组间临床妊娠率无统计学差异。结论:冷冻前≥6细胞胚胎的妊娠结局优于6细胞的胚胎;若冷冻前仅余1个6细胞的胚胎,虽然冻融后复苏率较低,但仍有妊娠的可能,因此仍然建议冻存这部分胚胎,提高患者的累积妊娠率。     

Postthaw blastomere survival is predictive of the success of frozen-thawed embryo transfer cycles

OBJECTIVE: To investigate the predictors of postthaw blastomere survival and the relationship of blastomere survival to the outcome of frozen-thawed embryo transfer (FET) cycles. DESIGN: Retrospective study. SETTING: An IVF unit in a tertiary care facility. PATIENT(S): Infertile women undergoing FET cycles with embryos cryopreserved on day 3 postinsemination. INTERVENTION(S): FET cycles. MAIN OUTCOME MEASURE(S): Embryo survival postthaw, pregnancy (PR), clinical pregnancy, and implantation rates. RESULT(S): A significant impact of postthaw blastomere survival on the outcome of FET cycles was noted. The thawed embryos in the low survival tertile resulted in significantly impaired implantation rate, clinical pregnancy rate, and PR compared to embryos in the high survival tertile. An inverse association was noted between serum P levels on the day of hCG administration and postthaw blastomere survival. CONCLUSION(S): We have demonstrated that postthaw blastomere survival is predictive of success of FET cycles. The relationship of poor postthaw embryo survival in the setting of elevated P is novel and not hitherto described.