Laser-assisted removal of necrotic blastomeres from cryopreserved embryos that were partially damaged

Objective: To examine whether the developmental potential of embryos that were partially damaged after freezing and thawing can be improved by removal of necrotic blastomeres before embryo transfer.

Design: Prospective pilot study and observational clinical series.

Setting: Private hospital.

Patient(s): Two hundred thirty-five infertile couples undergoing frozen embryo transfer.

Intervention(s): Removal of necrotic blastomeres from frozen-thawed human embryos.

Main Outcome Measure(s): Pregnancy and implantation rates.

Result(s): Removal of necrotic blastomeres from partially damaged frozen-thawed embryos before transfer increased rates of pregnancy (45.7% vs. 17.1%), ongoing pregnancy (40.0% vs. 11.4%) and ongoing implantation (16.2% vs. 4.3%) compared with the control group, in which necrotic blastomeres were not removed. A similarly high implantation rate (16.7%) was seen a subsequent clinical series in which necrotic blastomeres were removed from all partially damaged embryos.

Conclusion(s): The viability of partially damaged frozen-thawed embryos can be improved by removal of necrotic blastomeres before embryo transfer.     

Pronuclear stage cryopreservation after intracytoplasmic sperm injection and conventional IVF: implications for timing of the freeze

Objective: To compare clinical outcomes of frozen embryo transfers using cryopreserved pronuclear stage oocytes that had undergone either intracytoplasmic sperm injection (ICSI) or conventional IVF.

Design: Observational.

Setting: A tertiary referral reproductive medicine unit.

Patient(s): Couples undergoing either ICSI or conventional IVF from January 1, 1995 to December 31, 1997.

Intervention(s): Patients underwent a standard controlled ovarian hyperstimulation protocol and transvaginal ultrasound-guided oocyte retrieval. All normally fertilized (2PN) oocytes exceeding a specified embryo number designated for fresh transfer were immediately cryopreserved at the pronuclear stage. Our cryopreservation method included timing of the freeze according to pronuclear morphology. Subsequent frozen embryo thaw-transfer cycles were usually performed by thawing only the intended number of embryos for transfer.

Main Outcome Measure(s): Thaw survival rate, implantation rate, clinical pregnancy rate, delivery rate.

Result(s): Ninety-six thaw-transfer cycles (n = 72) and 93 thaw-transfer cycles (n = 67) were undertaken in patients who had previously undergone conventional IVF or ICSI, respectively. Embryo thaw survival rates (IVF, 90.4%; ICSI, 91.1%) were similar. Clinical pregnancy (IVF, 40.6%; ICSI, 44.1%) and delivery (IVF, 36.4%; ICSI, 39.8%) rates per transfer, as well as implantation (IVF, 19.1%; ICSI, 19.9%) rates, were also similar. There were only four clinical pregnancy losses in both groups.

Conclusion(s): Embryo thaw survival is similar for cryopreserved pronuclear stage oocytes derived from ICSI and conventional IVF. Clinical pregnancy, implantation and delivery rates were also similar for the two groups. In addition, there was no increase in the rate of pregnancy loss in ICSI patients after frozen embryo transfers.     

Clinical application of a new assisted hatching method using a piezo-micromanipulator for morphologically low-quality embryos in poor-prognosis infertile patients

Objective: To assess the effect of a assisted hatching technique using a piezo-micromanipulator on pregnancy rates in poor-prognosis infertile patients.

Design: A prospective randomized study.

Setting: The Infertility and IVF unit of the Kyoto University Hospital.

Patient(s): Infertile patients who had been treated for >4 years and failed in previous IVF trials at least twice.

Intervention(s): Two hundred forty-eight IVF cycles from 173 patients were divided into two groups: cycles with the transfer of embryos treated by assisted hatching and cycles with the transfer of nontreated embryos. Each group was subdivided into two groups according to embryo morphology: cycles in which three or two morphologically good-quality embryos were transferred and cycles in which one or no morphologically good-quality embryos were transferred. Assisted hatching was performed by a piezo-micromanipulator.

Main Outcome Measure(s): The clinical pregnancy rates and implantation rates.

Result(s): The clinical pregnancy and implantation rates were significantly higher in the assisted hatching group of patients with three or two good-quality embryos than in the other three groups.

Conclusion(s): The assisted hatching using a piezo-micromanipulator improved the pregnancy and implantation rates in poor-prognosis infertile patients with good-quality embryo transfer but had no effect in patients with low-quality embryo transfer.     

Embryonic factors affecting outcome from single cryopreserved embryo transfer

Multiple pregnancy minimization by single embryo transfer is becoming more prevalent, but is less common in the case of cryopreserved embryos. This study defines embryonic characteristics in single cryopreserved embryo transfers associated with success rates equivalent to those achieved when transferring two cryopreserved embryos. In a retrospective analysis of 6916 cryopreserved day-2 embryo transfer procedures, transfer of two cryopreserved embryos resulted in higher clinical pregnancy rates when compared with transfer of a single thawed embryo but was also associated with elevated multiple pregnancy rates (26.7% in women under 36). Optimal outcome (implantation rate of 30.9%) from single cryopreserved embryo transfer (SCET) in women under 36 was associated with cryopreservation at the 4-cell stage, loss of fewer than two blastomeres and subsequent cleavage of at least two surviving blastomeres. In comparison, transfer of two cryopreserved embryos in women under 36 resulted in pregnancy and implantation rates of 25.5 and 16.1% respectively. Interestingly, in cryopreserved 4-cell stage embryos, loss of a single blastomere did not reduce implantation potential and cleavage of only a single post-thaw blastomere was not indicative of increased implantation potential. Establishment of these critical thresholds provides a rational basis for SCET.     

A comparison of post-thaw results between cryopreserved embryos derived from intracytoplasmic sperm injection and those from conventional IVF

Objective: To study the effect of freezing on early stage embryos derived from intracytoplasmic sperm injection (ICSI) or from IVF.

Design: Prospective, controlled clinical study.

Setting: Private IVF center.

Patient(s): Sixty-seven consecutive patients undergoing frozen-thawed embryo transfer cycles.

Intervention(s): Early stage embryos were frozen, thawed, and transferred.

Main Outcome Measure(s): Post-thaw survival, implantation and pregnancy rates.

Result(s): We noted an 88% post-thaw survival rate, an 18% implantation rate, and a 52% pregnancy rate in the ICSI group and 81%, 11%, and 25%, respectively, with conventional fertilization.

Conclusion(s): Early stage embryos (either zygote or 2–4 cells) derived from ICSI can be frozen with confidence and higher post-thaw survival and pregnancy rates can be achieved when compared with those from conventional IVF.     

Introduction of blastocyst culture and transfer for all patients in an in vitro fertilization program

Objective: To evaluate the nonselective application of extended embryo culture on the outcome of IVF.

Design: Retrospective analysis.

Setting: Private practice assisted reproductive technology center.

Patient(s): Seven hundred ninety nonselected patients undergoing IVF with controlled ovarian stimulation.

Intervention(s): For day 3 ET, multicell embryos were cultured in human tubal fluid medium and 12% synthetic serum substitute. For day 5 ET, embryos were cultured for 48 hours in S1 medium and then for 48 hours in S2 medium.

Main Outcome Measure(s): Implantation rate (determined by total no. of visualized gestational sacs), ongoing pregnancy rate, and number of embryos available for ET.

Result(s): Respective day 3 and day 5 implantation rates for patients aged <35 years (29.5% and 38.9%), patients aged 35–39 years (20.7% and 28.2%), and all patients combined (23.3% and 32.4%) were statistically significantly different. Significantly more embryos were transferred on day 3 than on day 5 for patients aged <35 years (2.9 vs 2.4), patients aged 35–39 years (3.1 vs 2.6), and all patients combined (3.0 vs 2.5). The difference in ongoing pregnancy rates per retrieval was statistically significant for day 3 compared with day 5 transfers for all patients combined (35.9% vs 43.8%). Cancellation rates for transfer after retrieval increased significantly for day 3 compared with day 5 transfer (2.9% vs 6.7%).

Conclusion(s): These results demonstrate the feasibility of using extended embryo culture in a nonselective manner for couples undergoing IVF. Overall, extended embryo culture was associated with a significant increase in pregnancy rates and implantation rates and a significant decrease in the number of embryos transferred. The rate of multiple implantation among patients aged <35 years warrants consideration of single blastocyst transfers for this group.     

Factors affecting the success of human blastocyst development and pregnancy following in vitro fertilization and embryo transfer

Objective: To determine the factors affecting blastocyst development and pregnancy after IVF and ET.

Design: Retrospective analysis of data arising from a clinical trial.

Setting: Private in vitro fertilization clinic.

Patient(s): Fifty-six patients aged ≤40 years, undergoing IVF procedures for infertility, recruited specifically for blastocyst transfer.

Intervention(s): All zygotes were cultured to days 5 or 6 after insemination, and one to four of the most advanced blastocysts were transferred to the patient’s uterus.

Main Outcome Measure(s): Development of zygotes to blastocysts in vitro and pregnancy and implantation rates after ET.

Result(s): Fifty-one percent of all zygotes developed to blastocysts. Significant positive correlation between the number of blastocysts formed was observed with the number of oocytes, pronuclear zygotes, and eight-cell embryos formed. There was a negative correlation with male factor infertility. By day 5 or 6, 93% of the patients had at least one blastocysts, and the clinical pregnancy rate per transfer was 43% and the implantation per embryo transferred was 25%. No other clinical factor significantly affected the number of blastocysts formed, pregnancy rate, or implantation rate.

Conclusion(s): The numbers of oocytes, zygotes, and normally developing embryos in culture significantly affects the production of blastocysts in vitro. Male infertility significantly reduces blastocyst production. The number and the quality of the blastocysts transferred significantly influences clinical pregnancy rate.     

A randomized study comparing Crinone 8% and intramuscular progesterone supplementation in in vitro fertilization-embryo transfer cycles

Objective: To compare the efficacy of Crinone 8% intravaginal progesterone gel vs. IM progesterone for luteal phase and early pregnancy support after IVF-ET.

Design: Randomized, open-label study.

Setting: Academic medical center.

Patient(s): Two hundred and one women undergoing IVF-ET.

Intervention(s): Women were randomized to supplementation with Crinone 8% (90 mg once daily) or IM progesterone (50 mg once daily) beginning the day after oocyte retrieval.

Main Outcome Measure(s): Pregnancy, embryo implantation, and live birth rates.

Result(s): The women randomized to luteal phase supplementation with IM progesterone had significantly higher clinical pregnancy (48.5% vs. 30.4%; odds ratio [OR], 2.16; 95% confidence interval [CI], 1.21, 3.87), embryo implantation (24.1% vs. 17.5%; OR, 1.89; 95% CI, 1.08, 3.30), and live birth rates (39.4% vs. 24.5%; OR, 2.00; 95% CI, 1.10, 3.70) than women randomized to Crinone 8%.

Conclusion(s): In women undergoing IVF-ET, once-a-day progesterone supplementation with Crinone 8%, beginning the day after oocyte retrieval, resulted in significantly lower embryo implantation, clinical pregnancy, and live birth rates compared with women supplemented with IM progesterone.     

Day 3 versus day 5 embryo transfer: a prospective randomized study

Transfer of embryos at the blastocyst stage has been associated with exceptionally high implantation rates. There are, however, only a few prospective randomized studies comparing day 3 versus day 5 embryo transfer. Furthermore, the number of embryos replaced in the day 3 group transfer is often higher than the number of blastocysts replaced, thereby affecting implantation rates. A total of 118 patients undergoing standard IVF/intracytoplasmic sperm injection who had developed at least three 8-cell embryos showing <20% extracellular fragmentation on day 3 were randomized for day 3 or day 5 transfer. A maximum of two embryos were replaced. In this prospective, randomized study the implantation and pregnancy potential of embryos transferred on day 3 or day 5 were compared. Equal numbers of embryos were replaced in the two groups. There was no statistically significant difference between day 3 and day 5 transfer regarding positive human chorionic gonadotrophin rates (70 versus 67%), clinical pregnancy rates (61 versus 51%), implantation rates (44 versus 37%), twinning rates (42 versus 41%) and rates of early pregnancy loss (15 versus 29%). Transfer of embryos on day 3 or 5 showed similar implantation rates when equal numbers of embryos were transferred. Embryo transfer at the blastocyst stage seems to have no advantage over day 3 transfer in patients with more than two 8-cell embryos showing less than 20% fragmentation on day 3.     

Establishment of criteria for elective single embryo transfer at day 2 or day 3 by analyzing cases with successful implantation of all embryos transferred

AIM: Elective transfer of two good-quality embryos has been used to avoid triplet or high-order multiple pregnancies. However, the rate of twin pregnancies has remained fairly unchanged. In the present study, criteria for elective single embryo transfer (eSET) at day 2 or day 3 were established by analyzing cases with successful implantation of all embryos transferred. METHODS: A total of 685 fresh or frozen-thawed embryo transfers following in vitro fertilization/intracytoplasmic sperm injection between April 2002 and March 2006 were performed. Only embryo transfers at day 2 or day 3, but not at blastocyst stage, were included. Successful implantation of all embryos transferred was obtained in 17 pregnancy cycles. RESULTS: Thirty-one gestational sacs with fetal heartbeats were obtained by a total of 31 embryo transfers in 17 infertile women. The average age was 32.6 years (23-38), and 14 (82.3%) of the 17 women were <36 years old. Fifteen (88.2%) of the 17 pregnancies were established at the first attempt of assisted reproductive technology (ART). Of the 17 women, eight (47.1%) women were multigravida and four (23.5%) women were multipara. The indications for ART or insemination methods did not seem to be related to the pregnancy results. Twenty-nine (93.5%) of 31 embryos implanted were considered good-quality embryos. Of the 17 fresh embryos transferred at day 2, 15 were at the 4-cell stage and two were at the 5-cell stage. Of the 11 fresh embryos transferred at day 3, one was at the 6-cell stage, two were at the 7-cell stage and eight were at the 8-cell stage. CONCLUSION: The criteria for eSET at day 2 or day 3 were established as follows: <36 years of age, a first treatment cycle and more than two good-quality embryos developed at least to the 4-cell stage at day 2, or 6-cell stage at day 3. Additionally, the past history of pregnancy or delivery should be considered, as patients positive for such history might have better implantation ability. eSET can be highly recommended to avoid twin pregnancies in subjects with the established criteria.     

Blastocyst score affects implantation and pregnancy outcome: towards a single blastocyst transfer

Objective: To determine the relationship between blastocyst score and pregnancy outcome.

Design: Retrospective review of blastocyst transfer in an IVF clinic.

Setting: Private assisted reproductive technology unit.

Patient(s): 107 patients undergoing blastocyst culture and transfer of two embryos.

Intervention(s): Culture of all pronucleate embryos in sequential media to the blastocyst stage (day 5), followed by transfer of two blastocysts.

Main Outcome Measure(s): Implantation rates, pregnancy rates, and twinning were analyzed.

Result(s): When a patient received two top-scoring blastocysts (64% of patients), implantation and pregnancy rates were 70% and 87%, respectively. The twinning rate in this group was 61%. When only one top-quality blastocyst was available for transfer (21% of patients), the implantation and pregnancy rates were 50% and 70%. The twinning rate for this group was 50%. In contrast, when only low-scoring blastocysts were available for transfer (15% of patients), implantation and pregnancy rates were 28% and 44%, and the twinning rate was 29%. No monozygotic twins were observed in this group of patients.

Conclusion(s): The ability to transfer one high-scoring blastocyst should lead to pregnancy rates greater than 60%, without the complication of twins.     

ICSI and day 5 embryo transfers: higher implantation rates and lower rate of multiple pregnancy with prolonged culture

This retrospective review study, carried out in a private IVF clinic, compared pregnancy and implantation rates with day 3 versus day 5 embryo transfers in a selected group of patients. Participants were patients who failed to achieve pregnancy in at least one previous attempt with embryo transfer on days 2 or 3, and had more than five oocytes fertilized. A total of 296 patients who had undergone day 3 (group A) transfers were compared with 154 who had undergone day 5 transfers (group B). Interventions were intracytoplasmic sperm injection (ICSI), day 3 and day 5 embryo transfer. Outcome measures were pregnancy, implantation, multiple gestation and blastocyst formation rates. Overall, 86.4% of embryos were at the six- to eight-cell stage at 72 h and 30% developed to blastocyst by day 5. The mean number of embryos transferred was 4.0 on day 3 and 3.0 on day 5. Pregnancy and implantation rates were 34.8 and 11.5% in group A, versus 45.3 and 18.5% in group B. Multiple gestation rate was 47.1% in group A and 28.5% in group B. Prolonging embryo culture in vitro to day 5 improved embryo selection and implantation rates. A significant decrease in high order gestations was achieved by reducing the number of embryos transferred, without compromising the pregnancy rates.     

Importance of the biopsy date in autologous endometrial cocultures for patients with multiple implantation failures

Objective: To analyze the effectiveness of autologous endometrial coculture by the cycle day of the endometrial biopsy.

Design: Retrospective study.

Setting: University-based IVF center.

Patient(s): Two hundred eight patients with multiple IVF failures.

Intervention(s): Embryos were split and randomly allocated to growth on autologous endometrial coculture or conventional media.

Main Outcome Measure(s): Embryo quality and pregnancy outcome.

Result(s): The overall clinical pregnancy rate was 41.8%. Embryos grown on autologous endometrial coculture were of higher quality (more blastomeres and less fragmentation) than embryos grown with conventional media. Early luteal biopsies (<5 days after LH surge) for autologous endometrial coculture did not demonstrate an improvement in embryo quality as compared to the significant improvement demonstrated with later luteal endometrial biopsies (≥5 days after LH surge). The date of the biopsy was predictive of pregnancy outcome when using autologous endometrial coculture (44.7% [≥5 days after LH surge] vs. 18.8% [<5 days after LH surge], P=.012).

Conclusion(s): We have demonstrated an improvement in embryo quality when using autologous endometrial coculture. The improvement in embryo quality and higher pregnancy rates were limited to biopsies ≥5 days after the LH surge. This suggests that mid/late luteal phase endometrium contains factors that enhanced embryo growth and subsequent implantation.     

The effect of retained embryos on pregnancy outcome in an in vitro fertilization and embryo transfer program

OBJECTIVE: The purpose of this study was to determine the incidence of retained embryos and its impact on pregnancy outcome in the absence of known risk factors like blood and mucus in the transfer catheter. The factors that could be associated with embryo retention were also investigated. STUDY DESIGN: The results of all embryo transfer procedures performed at Ankara IVF Center between January 2003 and December 2005 were analyzed retrospectively. Three hundred and five embryo transfers, in which the transfer catheter was contaminated with blood or mucus, were excluded and the remaining 1,454 embryo transfers, with clean catheter, were enrolled into the study. Both fresh (n=1,422) and frozen (n=32) embryo transfers were included. RESULTS: The overall incidence of retained embryos during study period was 2.8% (41/1,454) following a clean initial embryo transfer. The mean age of the female partner, mean number of retrieved oocytes, MII oocytes, fertilized oocytes and the embryos transferred were similar in patients with and without retained embryos. The 1,454 embryo transfers performed during the study period resulted in 712 pregnancies (49%), of which 639 proved to be clinical pregnancies with a rate of 44%. The implantation rate was 22.8%. Pregnancy outcomes including positive beta-hCG (58.5% versus 48.7%), biochemical (4.7% versus 5.1%) and clinical pregnancy rates (53.6% versus 43.6%), implantation rate (24% versus 22.7%) and multiple pregnancy rate (36.3% versus 44.7%) were not significantly different between patients with and without retained embryos. An influence of individual physicians and embryologists on the frequency of retained embryos was not detected. The type of embryo transfer catheter used did not show any difference in terms of embryo retention. The cleavage stages of embryos were not different between groups. Although it was not statistically significant, the number of embryos transferred appeared to be a potentially confounding factor for retained embryos (p=0.053) and it might be significant in a slightly larger sample. When transfer of one or two embryos was compared to three or more embryos, the likelihood of retained embryos increased from 1.2% (4/321) to 3.2% (37/1,133). CONCLUSION: Retained embryos in the transfer catheter and immediate retransfer of them have no adverse impact on clinical pregnancy and implantation rates unless other previously reported signs of difficult transfer are also observed.     

Blastocyst transfer: a useful tool for reduction of high-order multiple gestations in a human assisted reproduction program

OBJECTIVE: We evaluated the efficacy of blastocyst transfer in decreasing the incidence of high-order multiple gestations after in vitro fertilization. STUDY DESIGN: We conducted a retrospective analysis of 218 patients who were undergoing in vitro fertilization and by our criteria of three 8-cell embryos on day 3 could receive either a day 3 transfer of cleaved embryos or a day 5 transfer of blastocysts. Ongoing pregnancy rates, implantation rates (determined by the total number of visualized gestational sacs), and multiple pregnancy rates were compared between the 2 groups. RESULTS: Respective day 3 and day 5 ongoing pregnancy rates (61% and 51%) and implantation rates (35% and 33%) were not significantly different. There were 9 triplet or higher gestations in the day 3 group and 0 in the day 5 group. CONCLUSION: Blastocyst transfer can be used to reduce the number of embryos transferred and the resultant incidence of high-order multiple pregnancies while maintaining high pregnancy rates.     

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。     

胚胎发育速度及形态评级和受精卵原核评级联合选择移植胚胎的研究

目的探讨胚胎发育速度及形态评级并参考受精卵原核评级（联合评级）,对行体外受精-胚胎移植及卵母细胞质内单精子注射后移植胚胎筛选的意义.方法回顾性分析我院2003年5-12月,采用联合评级筛选进行胚胎移植的434个周期,共2714个正常受精卵的资料.根据受精卵原核发育是否同步,分为原核发育同步组和原核发育不同步组,观察不同原核等级受精卵的发育潜力;首先根据胚胎发育速度及形态评级,再根据受精卵原核等级的联合评级选择移植胚胎.根据移植胚胎中是否含有原核发育同步的胚胎,比较原核发育同步组与原核发育不同步组受精卵进行胚胎移植后的临床妊娠率和着床率.结果2714个正常受精卵中,原核发育同步组受精卵1774个,其中优质胚胎743个,优质胚胎率为41.88%;原核发育不同步组受精卵940个,其中优质胚胎319个,优质胚胎率为33.94%,两组比较,差异有统计学意义（P＜0.01）.原核发育同步组中胚胎移植周期395个,临床妊娠率为47.85%（189/395）,着床率为27.49%（273/993）;原核发育不同步组中胚胎移植周期39个,临床妊娠率为43.59%（17/39）,着床率为25.00%（21/84）.两组比较,差异无统计学意义（P＞0.05）.结论采用联合评级,受精卵原核发育同步组与发育不同步组胚胎的临床妊娠率及着床率无差异;参考原核评级不能预测更高的妊娠率和着床率,但能预测胚胎发育的潜力.     

年龄及移植优质胚胎数对体外受精-胚胎移植患者多胎妊娠率的影响

目的 研究年龄及移植优质胚胎数对体外受精-胚胎移植(IVF-ET)患者多胎妊娠发生率的影响.方法 回顾性分析2004年1月至2006年11月,在中南大学中信湘雅生殖与遗传专科医院行新鲜胚胎移植的不孕症患者共4395个周期,按患者年龄分为年龄<35岁组(3442个周期)和年龄≥35岁组(共953个周期).每个周期常规移植2～3枚胚胎,仅有1枚可移植胚胎者移植1枚胚胎,年龄≥135岁或第2次移植且只有2枚胚胎者移植2枚胚胎.统计各组所有周期的临床妊娠及多胎妊娠率.结果 (1)年龄<35岁组移植1枚胚胎者的临床妊娠率[29.64%(166/560)]低于移植2、3枚者[分别为51.63%(1315/2547)、52.84%(177/335)],差异均有统计学意义(P<0.01);移植2枚与3枚者比较,差异无统计学意义(P>0.05).3者的多胎妊娠率分别为21.08%(35/166)、31.41%(413/1315)和42.37%(75/177),两两比较,差异均有统计学意义(P<0.01).(2)年龄≥35岁组移植1枚胚胎者的临床妊娠率[19.07%(41/215)]低于移植2、3枚者[分别为33.70%(92/273)、39.14%(182/465)],差异均有统计学意义(P<0.01);移植2枚与3枚者比较,差异无统计学意义(P>0.05).移植1枚和2枚胚胎者的多胎妊娠率[分别为19.51%(8/41)和20.65%(19/92)]比较,差异无统计学意义(P>0.05);2者均低于移植3枚胚胎者[40.66%(74/182)],差异有统计学意义(P<0.01).(3)年龄<35岁组的临床妊娠率[48.17%(1658/3442)]高于年龄≥35岁组[33.05%(315/953)],差异有统计学意义(P<0.01);年龄<35岁组移植1、2和3枚胚胎者的临床妊娠率分别与年龄≥35岁组移植相应胚胎数者比较,差异均有统计学意义(P<0.01).两组的多胎妊娠率[分别为31.54%(523/1658)和32.06%(101/315)]比较,差异无统计学意义(P>0.05).结论 IVF-ET患者移植2枚优质胚胎与移植3枚优质胚胎的临床妊娠率相近,但多胎妊娠率降低.年龄对多胎妊娠率无影响.     

Success rates following intracytoplasmic sperm injection are improved by using ZIFT vs IVF for embryo transfer

Purpose: The purpose of this study was to analyze whether the mode of embryo transfer (ZIFT vs IVF) affected the outcome in intracytoplasmic sperm injection (ICSI) cycles. Methods and Results: Eighty-two ICSI cycles (42 ZIFT and 40 IVF) were analyzed. Several variables, including patient age and weight, numbers of mature eggs collected, injected, and fertilized, fertilization rate, number of fertilized eggs obtained per cycle, numbers of zygotes/embryos transferred, clinical pregnancy rate, and implantation rate, were compared. Mean patient age and weight were identical. The mean number of mature eggs collected and injected and fertilization rate were significantly higher in the ZIFT group, however, the mean numbers of zygotes/embryos transferred were identical. The clinical pregnancy and implantation rates in ZIFT cycles (52.3 and 23.2% respectively) were significantly higher than in IVF cycles (17.5 and 9.7%). Conclusions: These data suggest that ZIFT is the more appropriate method for transfer of ICSI-derived embryos.     

培养液中添加不同促性腺激素对卵母细胞体外成熟的影响

目的:比较卵母细胞体外成熟培养液中添加不同促性腺激素对未成熟卵母细胞体外成熟结局的影响。方法:将行卵母细胞体外成熟(IVM)的35例患者共42个新鲜取卵周期,随机分成A组:22个取卵周期将重组人促卵泡激素(果纳芬,rFSH)和重组人绒毛膜促性腺激素(艾泽,hCG)按1∶1的比例混合添加,终浓度为75 mIU/ml;B组:20个取卵周期添加终浓度为75 mIU/ml的尿源性促性腺激素(hMG),进行未成熟卵母细胞体外成熟培养。35例患者中新鲜取卵周期未移植或移植后未孕者行解冻胚胎移植。比较组间患者的卵母细胞成熟率、受精率、卵裂率、优质胚胎率、累计临床妊娠率及胚胎着床率。结果:取卵均于月经周期第12日或最大卵泡发育至10￣12 mm时进行,故所获卵均为未成熟卵。A组获卵181枚,经培养后成熟84枚,行卵胞浆内单精子注射(ICSI)84枚,受精60枚,卵裂55枚,优质胚胎20枚;新鲜胚胎移植9例,获1例临床妊娠,解冻胚胎移植5例,获1例临床妊娠,累计临床妊娠率为14.29%,胚胎着床率为7.14%。B组获卵176枚,经培养后成熟120枚,行ICSI 120枚,受精97枚,卵裂90枚,优质胚胎41枚,新鲜胚胎移植6例,获4例临床妊娠,解冻胚胎移植9例,获3例临床妊娠,累计临床妊娠率为46.67%,胚胎着床率为33.33%。结论:卵母细胞体外成熟培养液中添加尿源性促性腺激素可获得较添加重组人促卵泡激素和重组人绒毛膜促性腺激素高的卵母细胞成熟率、临床妊娠率及胚胎着床率。