移植時囊胚的重新擴張狀態似乎並不顯示它們在任何時間間隔內的植入潛力

The re-expansion status of the blastocysts at the transfer seems not to be indicative of their implantation potential in any of the time intervals 

OSTER PRESENTATION| VOLUME 111, ISSUE 4, SUPPLEMENT , E26-E27, APRIL 2019

The blastocyst re-expansion status after thawing do not seem to affect the clinical outcomes in freeze all preimplantation genetic testing (PGT) cycles

Background

The integrity and formation of the blastocyst cavity (blastocoel) is maintained by the sodium pump (Na+/K+-ATPase), which gradually increases fluid accumulation and pressure on both TE and zona pellucida (ZP).

When the blastocyst collapses after manipulations like biopsy and/or vitrification, the blastocoel gradually re-expands regaining fluid accumulation and pressure on both the TE and ZP.

The degree of re-expansion is considered one indicator of the recovery status for frozen blastocysts and some studies have shown that fast re-expanding blastocysts have superior pregnancy rates, while others failed to find any correlation between the re-expansion speed and the implantation rate of frozen blastocysts.

Moreover, the dynamics of re-expansion of frozen biopsied blastocyst can be different than blastocysts that were simply collapsed or left intact before freezing.

Objective

The aim of our study was to determine the implantation rate of euploid frozen blastocyst according to their re-expansion status after different time intervals between the warming and the transfer.

Material and methods

Retrospective single center cohort study.

Study period: July 2018 – September 2018.

Warming time and transfer time were recorded for each FET cycle.

Only patients transferring euploid blastocysts of consistent quality were included.

Embryos were assessed 3 times: right after, 1h after warming, and right before the transfer. Blastocyst with dark, granular appearing cells and large areas of degeneration were identified as nonsurviving. In terms of re-expansion, blastocyst were classified as Collapsed (C): no sign of re-expansion; Re-Expanding (RE): showing sign of re-expansion; re-Expanded (E): re-expanded at the same grade as before biopsy/freezing; Hatching (H): herniating from the zona pellucida or fully hatched.

Patients were divided in 4 groups according to the time interval between the warming and the embryo transfer (< 3h, >3h, <5h, >5h) and matched between the groups <3h and > 3h, and <5h and > 5h for female age (+/-1 year), number of embryo transferred, use of gestational carrier and/or egg donor and day of freezing.

Expansion Rate at the transfer, Clinical Pregnancy Rate (CPR), Implantation Rate (IR) and Abortion Rate (AR) were evaluated.

Fisher’s exact test was used for statistical analysis.

Results

The results are reported in Table 1.

Table 1Clinical outcomes according to the re-expansion grade at the different time intervals between embryo warming and transfer.

	< 3h	>3h		<5h	>5h
N° Cycles	34	98		73	39
Average age	39,5±6.4	39,0±5,9	ns	38,6±6,1	39,7±6,2	ns
Average interval	2h14’±32’25’’	4h35’±1h7’4’’		3h23’±54’18’’	6h8’±1h3’59’’
∗ C at thawing	4 (9,0%)	10 (8,0%)		7 (8,6%)	2 (4,5%)
∗ C implanted	3/4 (75%)	3/10 (30%)	ns	3/7 (42,8%)	1/2	ns
∗ RE at thawing	6 (13,6%)	1 (0.8%)		5 (6,2%)	0
∗ RE implanted	4/6 (66,7%)	1/1	ns	4/5 (80%)	0
∗ E at thawing	26 (61,4%)	55 (44,0%)		52 (64,4%)	14 (31,8%)
∗ E implanted	18/26 (69,2%)	35/55 (63,6%)	ns	37/52 (71,2%)	9/14 (64,3%)	ns
∗ H at thawing	8 (15,9%)	59 (47,2%)		17 (21%)	28 (63,6%)
∗ H implanted	5/7 (71,4%)	38/59 (64,4%)	ns	14/17 (82,4%)	23/28 (83,1%)	ns
IR	30/44 (68.2%)	77/125 (61,6%)	ns	58/81 (71,6%)	33/44 (75,0%)	ns
CPR	27/34 (79.4%)	67/98 (68,4%)	ns	53/73 (72,6%)	30/39 (76,9%)	ns
AR	5/30 (16.6%)	6/77 (7,8%)	ns	7/58 (12,0%)	1/33 (3%)	ns

∗ C=collapsed: no sign of re-expansion; RE= Re-Expanding: showing sign of re-expansion; E= re-Expanded: re-expanded at the same grade as before biopsy/freezing; H= Hatching: herniating from the zona pellucida or fully hatched.

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Conclusions

The re-expansion status of the blastocysts at the transfer seems not to be indicative of their implantation potential in any of the time intervals we considered. Since we included only patients with consistent quality euploid embryos, we can infer that the embryo characteristic before the freezing are the most indicative of their implantation potential.

Moveover, clinical outcomes didn’t seem to change for delayed transfers, with general results being comparable in any of the time intervals analyzed.

Interestingly, collapsed blastocyst can still implant after >5h from the warming, although our numbers are too low to understand if their implantation potential is impaired.

周末假日  vs  平日施行IVF-ET

取卵 鮮胚或凍胚胚胎植入懷孕率並無差異

. 2023 Sep;40(9):2091-2099.

  

Outcomes of assisted reproductive technology procedures performed on weekdays versus weekends: a retrospective cohort study

Purpose: To evaluate if assisted reproductive technology (ART) outcomes are different based on whether procedures - oocyte retrieval, insemination, embryo biopsy, or embryo transfer - are performed on a weekday versus weekend/holiday.

Methods: Retrospective cohort study of all patients ≥ 18 years old who underwent oocyte retrieval for in vitro fertilization or oocyte banking (n = 3,197 cycles), fresh or natural-cycle frozen embryo transfers (n = 1,739 transfers), or had embryos biopsied for pre-implantation genetic testing (n = 4,568 embryos) in a large academic practice from 2015-2020. The primary outcomes were as follows: oocyte maturity for oocyte retrievals; fertilization rate for insemination; rate of no result on pre-implantation genetic testing for embryo biopsy; and live birth rate for embryo transfers.

Results: The average number of procedures performed per embryologist per day was higher on weekends/holidays than weekdays. For oocyte retrievals performed on weekdays vs. weekends/holidays, there was no difference in oocyte maturity rate (88% vs 88%). There was no difference in the fertilization rate (82% vs 80%) in cycles that had intracytoplasmic sperm injection performed on weekdays vs. weekends/holidays. No difference was found in the no result rate for embryos biopsied on weekdays vs. weekends/holidays (2.5% vs 1.8%). Finally, there was no difference by weekday vs. weekend/holiday in the live birth rate per transfer among all transfers (39.6% vs 36.1%), or when stratified by fresh (35.1% vs 34.9%) or frozen embryo transfer (49.7% vs. 39.6%).

Conclusion: We found no differences in ART outcomes among women who had their oocyte retrievals, inseminations, embryo biopsies, or embryo transfers performed on weekdays versus weekends/holidays.

與單一 hCG 或 GnRHa 觸髮劑相比，合併施用 GnRHa 和 hCG 作為雙重破卵可增加優質胚胎的數量，但與獲得的卵母細胞數量無關。也與懷孕率無關

• Co-administration of GnRHa and hCG as a dual trigger increases the number of good-quality embryos but it is not associated with a higher number of oocytes retrieved, compared with single hCG or GnRHa trigger.
• The live birth rate and ongoing pregnancy rate after frozen ET in the dual trigger group were significantly higher than those in the GnRHa group (32.6% vs 14.1%, P = 0.007 and 34.8% vs 17.6%, P = 0.013, respectively), but not superior to those in the hCG group (32.6% vs 27.9%, P = 0.537 and 34.8% vs 27.9%, P = 0.358, respectively).
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Ovulation triggering with hCG alone, GnRH agonist alone or in combination? A randomized controlled trial in advanced-age women undergoing IVF/ICSI cycles 

Human Reproduction, Volume 37, Issue 8, August 2022, Pages 1795–1805, https://doi.org/10.1093/humrep/deac114

Is a dual ovulation trigger with a combination of GnRH agonist (GnRHa) and hCG superior to single hCG and/or single GnRHa trigger in improving treatment outcomes in advanced-age women (aged ≥ 35 years) undergoing IVF/ICSI treatment?

SUMMARY ANSWER

Co-administration of GnRHa and hCG as a dual trigger increases the number of good-quality embryos but it is not associated with a higher number of oocytes retrieved, compared with single hCG or GnRHa trigger.

WHAT IS KNOWN ALREADY

Many studies have demonstrated that a dual trigger has positive impact on oocyte maturation, retrieval rate and pregnancy rate without increasing the risk of ovarian hyperstimulation syndrome (OHSS) in some groups of IVF patients, when compared with single hCG trigger. Few studies have however been conducted to compare a dual trigger with a single GnRHa trigger, and insufficient evidence exists to support which trigger can achieve the best outcomes in IVF patients aged ≥35 years.

STUDY DESIGN, SIZE, DURATION

This was an open-label randomized controlled trial of 510 participants conducted at single reproductive medical center from January 2019 to December 2021. After a sample size calculation performed by retrospectively analyzing our previous clinical data, we planned to recruit 170 patients in each group and 510 patients in total for the study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women aged ≥35 years undergoing IVF/ICSI treatment, receiving a non-pituitary down-regulation protocol, and with low risk of OHSS, were enrolled in this trial. On the trigger day, patients were randomized into three groups: hCG alone (who received 6000 IU of hCG), GnRHa alone (who received 0.2 mg of triptorelin) and dual trigger (who received 0.2 mg of triptorelin plus 2000 IU of hCG) groups. The primary outcome parameter was the number of retrieved oocytes. The secondary outcome parameters included, among others, the number and rates of mature oocytes, two pronuclei (2PN) embryos and good-quality embryos, as the rates of OHSS, clinical pregnancy, miscarriage and live birth.

MAIN RESULTS AND THE ROLE OF CHANCE

There were no significant differences in the baseline demographic characteristics among the three groups. The dual trigger was associated with a higher retrieval rate (87.9% vs 84.1% in the hCG group, P = 0.031; 87.9% vs 83.6% in the GnRHa group, P = 0.014). However, the number of retrieved oocytes in the dual trigger group was comparable with those in the hCG group (4.08 ± 2.79 vs 3.60 ± 2.71, P = 0.080) and the GnRHa group (4.08 ± 2.79 vs 3.81 ± 3.38, P = 0.101); comparable data between the groups were also found when analyzing the number of 2PN embryos and the 2PN rate. In the dual trigger group, the numbers of good-quality embryos and viable embryos were both significantly higher than in the hCG group (1.74 ± 1.90 vs 1.19 ± 1.45, P = 0.016 and 2.19 ± 2.11 vs 1.56 ± 1.66, P = 0.008, respectively) and the GnRHa group (1.74 ± 1.90 vs 1.20 ± 1.67, P = 0.003 and 2.19 ± 2.11 vs 1.45 ± 1.75, P = 0.001, respectively). Pregnancy outcomes after fresh embryo transfer (ET) were comparable between the groups. The live birth rate and ongoing pregnancy rate after frozen ET in the dual trigger group were significantly higher than those in the GnRHa group (32.6% vs 14.1%, P = 0.007 and 34.8% vs 17.6%, P = 0.013, respectively), but not superior to those in the hCG group (32.6% vs 27.9%, P = 0.537 and 34.8% vs 27.9%, P = 0.358, respectively).

原核移植預防線粒體DNA疾病的臨床應用

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5131843/

• 粒線體（Mitochondria）是在細胞中產生能量的重要胞器，擁有自己的環狀DNA（mtDNA）及基因組。相較於細胞核基因體（Nuclear genome）具33億鹼基對、約2萬個基因，粒線體基因體（mitochondrial genome）僅有16,569個鹼基對、37個基因，主要負責人體細胞行呼吸作用以產生能量的功能[1]。
• 當粒線體當中的基因產生突變時，可造成能量密集型組織如大腦、心臟、肝臟以及肌肉等功能的異常與損害。許多粒線體疾病是無藥可治且致命的，比如導致中樞神經系統發生退化性損傷的兒童罕見疾病：萊氏綜合症（Leigh syndrome），罹患此病的孩童多於2至3歲前死亡[2]。
• 孩童粒線體的唯一來源為母親，因受精時位於精子尾部的粒線體並不會進入卵子，故子代的粒線體皆來自卵子細胞質中的粒線體，若母親的粒線體DNA具有致病突變，此突變極可能遺傳至子女。
• 粒線體置換療法（mitochondrial replacement therapy, MRT）為一種輔助生殖技術，利用捐贈者的正常粒線體來替換卵子或胚胎中有缺陷的粒線體，使攜帶罕見遺傳疾病基因的婦女有機會生下健康的嬰兒。但這也意味著後代將攜帶來自「一父二母」三親的DNA，
• 「三親嬰兒」體內絕大部分的DNA（超過99.8%）依舊來自他們的父母，但還有大約0.1%的遺傳物質來自粒線體捐贈女性，而該項療法預估將可有效防止腦損傷、肌肉萎縮等重大遺傳性疾病的發生。

• PNT 後，大多數 (79%) 囊胚中的 mtDNA 殘留量減少至 <2%。
• PNT 有可能降低 mtDNA 疾病的風險，但可能無法保證預防。
• 減數分裂完成後不久移植 PN 可以提高存活率。
• 早期 PNT (ePNT) 可促進生存（92% vs 晚期 PNT 59%）。
• 與 LtPNT 相比，ePNT 受精卵存活率的提高（系列 I）改善了囊胚的形成
•  ePNT不會導致非整倍體囊胚發生率增加。
• ePNT 受精卵表現出正常的 PN 鄰接和分裂至 2 細胞階段，表明精子中心粒功能沒有被破壞。
• 患者卵母細胞而不是供體卵母細胞的玻璃化冷凍可能會最大限度地減少線粒體 DNA 殘留。
• 患者卵母細胞變得容易受到與年齡相關的減數分裂非整倍體影響之前儲存患者卵母細胞的額外優勢

Towards clinical application of pronuclear transfer to prevent mitochondrial DNA disease

• This promotes efficient development to the blastocyst stage with no detectable effect on aneuploidy or gene expression. 
• After optimization, mtDNA carryover was reduced to <2% in the majority (79%) of PNT blastocysts. 
• The importance of reducing carryover to the lowest possible levels is highlighted by a progressive increase in heteroplasmy in a stem cell line derived from a PNT blastocyst with 4% mtDNA carryover.
• PNT has the potential to reduce the risk of mtDNA disease, but it may not guarantee prevention.
• Transplantation of the nuclear genome between oocytes arrested at metaphase of meiosis II (MII) is associated with a high incidence of abnormal fertilization. 
• Our data indicate that early PNT (ePNT) promotes survival (92% vs 59% for late PNT). 
• ePNT zygotes showed normal PN abuttal and division to the 2-cell stage, indicating that sperm centriole function was not disrupted.
• Increased survival of ePNT zygotes (Series I) resulted in improved blastocyst formation compared with LtPNT
•  ePNT procedure does not result in an increased incidence of aneuploid blastocysts.
• Transplanting the PN shortly after completion of meiosis resulted in improved survival. 
•  Vitrification of patient rather than donor oocytes will likely minimize mtDNA carryover.
• This offers the added advantage of stockpiling patient oocytes before they become susceptible to age-related meiotic aneuploidy