Effect of ovarian stimulation on developmental speed of preimplantation embryo in a mouse model

Ovarian stimulation protocols are widely used to collect oocytes in assisted reproductive technologies (ARTs). Although the influence of ovarian stimulation on embryo quality has been described, this issue remains controversial. Here, we analyzed the influence of ovarian stimulation on developmental speed and chromosome segregation using live cell imaging. Female mice at the proestrus stage were separated by the appearance of the vagina as the non-stimulation (-) group, and other mice were administered pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) as the stimulation (+) groups. The cumulus-oocyte complexes from both groups were inseminated with sperm suspensions from the same male mice. Fertilization rates and developmental capacities were examined, and the developmental speed and frequency of chromosome segregation errors were measured by live-cell imaging using a Histone H2B-mCherry probe. The number of fertilized oocytes obtained was 1.4-fold more frequent in the Stimulation (+) group. The developmental rate and chromosome stability did not differ between the groups. Image analysis showed that the mean speed of development in the stimulation (+) group was slightly higher than that in the non-stimulation (-) group. This increase in speed seemed to arise from the slight shortening of the 2- and 4-cell stages and third division lengths and consequent synchronization of cleavage timing in each embryo, not from the emergence of an extremely rapidly developing subpopulation of embryos. In conclusion, ovarian stimulation does not necessarily affect embryo quality but rather increases the chances of obtaining high-quality oocytes in mice.

Beyond appearance: Can morphologically low-grade euploid blastocysts yield successful pregnancies?

Purpose

The primary objective of this investigation is to evaluate how morphological quality affects the pregnancy outcomes in euploid embryos determined by preimplantation genetic testing for aneuploidies (PGT-A). Concurrently, as a secondary objective, we aim to identify which specific aspects of morphological evaluation exert the most significant impact on these outcomes.

Methods

A retrospective analysis of 451 single euploid embryo transfer cycles at our clinic was conducted. Embryos were evaluated based on the degree of blastocyst expansion, inner cell mass (ICM), trophectoderm (TE) morphology, and the day of blastocyst vitrification. Outcomes between morphologically low-grade and high-grade embryos were compared. Additionally, the study analyzed which morphological factors most influenced pregnancy outcomes.

Results

Pregnancy outcomes were significantly lower in morphologically low-grade blastocysts compared to high-grade ones. Among the morphological evaluations, the ICM assessment was significantly associated with the live birth rate.

Conclusion

Our study indicates that the morphological quality of euploid embryos, particularly the evaluation of the ICM, plays a crucial role in IVF-ET success.

Microscopic Epididymal Sperm Aspiration (MESA) Should be Employed Over Testicular Sperm Extraction (TESE) Sperm Retrieval Surgery for Obstructive Azoospermia (OA)

INTRODUCTION

 Testicular sperm extraction (TESE) has been widely used as a sperm extraction surgery for azoospermia even for obstructive azoospermia (OA) because it does not require surgical skill. However, there are postoperative pain issues, and subsequent testicular atrophy and decreased testosterone levels may occur with TESE. This study examines the usefulness of microscopic epididymal sperm aspiration (MESA) for OA.

METHODS

 We studied 108 patients diagnosed with OA and treated with MESA at our institute between April 2004 and December 2021. The MESA was performed using a micropipette with a micropuncture technique under an operative microscope. When no sperm were present or motility was not observed, additional punctures to the epididymal tubule were performed.

RESULTS

 Motile sperm were recovered in all cases (108 cases). Of these, intracytoplasmic sperm injection (ICSI) using frozen-thawed sperm was performed in 101 cases and the normal fertilization rate was 76.2%. A total of 436 embryo transfer (ET) cycles were performed. The implantation rate per transfer cycle was 47.9%, the clinical pregnancy rate was 41.0%, and the live birth rate was 23.7%. The per-case live birth rate was 84.8%.

CONCLUSIONS

 MESA-ICSI has a very good fertilization rate, clinical pregnancy rate, and delivery rate. Furthermore, the patient's postoperative pain is less, the number of sperm collected is larger, the burden on the embryologist who processes the collected sperm is less, and ICSI can be easily attempted after frozen-thawed sperm. MESA rather than TESE should be employed for the OA subjects.

Infertility treatment for patients having a microdeletion of azoospermic factor (AZF)

In genetic causes of male infertility, Y chromosome microdeletions are the second most common after Klinefelter's syndrome. Although sperm recovery rate is relatively high for subjects with azoospermic factor (AZF) c chromosome microdeletion, intracytoplasmic sperm injection (ICSI) results using retrieved sperm has been reported to be poor. We retrospectively examined the infertility treatment for subjects with AZF microdeletion. From October 2017 to September 2020, chromosomal examination of 67 azoospermic subjects and 12 cryptozoospermia were performed. Of these, twenty-three subjects (29.1%) had AZF microdeletion. Twelve subjects with AZFc microdeletion and one subtype with unknown classification (Ym-9; P3 deletion) received sperm retrieval surgery due to azoospermia. Two subjects obtained motile sperm by microscopic epididymal sperm aspiration (MESA) and four subjects by microscopic testicular sperm extraction (micro-TESE). Pregnancy and healthy delivery were achieved in 6 of 14 subject (42.9%; including one twin) using ICSI. This was comparable with previous reports. Since there were two cases of obstructive azoospermia, we employed MESA to avoid testicular damage. Following observation of the testis and epididymis under operative microscope, a decision was made to perform sperm retrieval surgery to avoid unnecessary testicular damage. Furthermore, since AZFc microdeletion is passed to the next generation, long term follow-up is necessary.

Cryptozoospermia: Should we use ejaculated sperm or surgically retrieved sperm for assisted reproductive technology?

Purpose

In cryptozoospermic subjects, it may often may be difficult to secure motile sperm for assisted reproductive technology (ART). We examined the results of ART with frozen thawed ejaculated sperm in cryptozoospermic subjects and evaluated whether sperm retrieval surgery is necessary for such patients in our clinic.

Methods

Between 2013 and 2021, we evaluated 197 cryptozoospermic patients. Age, endocrine panel at the time of the initial semen analysis, and anti-müllerian hormone levels at the time of the spouse's first egg retrieval were examined. Cryopreservation of ejaculated motile sperm collected essentially weekly over a 3-month period was carried out. ART data recorded was the number of egg retrieval cycles, normal fertilization rate, and clinical pregnancy rate.

Results

ART using frozen sperm as well as sperm ejaculated on the day of egg retrieval was possible in all cases. The normal fertilization rate was 70.4%, the clinical pregnancy rate per embryo transferred was achieved in 31.5% (870 cycles), and the live birth rate per case was 73.8%.

Conclusions

Intracytoplasmic sperm injection (ICSI) was possible without sperm retrieval surgery in cryptozoospermia, resulting in 73.8% of live births per patient. Sperm identification, sperm processing, and ICSI technique are especially important in cryptozoospermia. Sperm retrieval surgery can be avoided in cryptozoospermic patients.

Evaluation of the serum zinc concentration in male infertility patients: an analysis of 2010 cases

Zinc is an important trace element, and its importance for male infertility has been reported. The aim of the study was to assess whether the serum zinc concentrations were related to semen quality in male infertility patients. In 2010 subjects who consulted at our male infertility clinic between November 2018 and May 2021, serum zinc concentrations were assessed along with age, sperm concentration, sperm motility, endocrine panel, and body mass index (BMI). A normal zinc concentration was observed in 1069 (53.2%), subclinical deficiency in 845 (42.0%), and deficiency in 79 subjects (3.9%). On the other hand, high a zinc level was observed in only 17 subjects (0.9%). The serum zinc concentration did not relate with age, sperm concentration, sperm motility, luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone, and body mass index (BMI). However, normozoospermic subjects showed significantly higher zinc concentrations than among azoospermic (included non-obstructive; NOA and obstructive; OA) and cryptozoospermic patients. Furthermore, the zinc concentration was lower in NOA subjects when comparing to oligozoospermia and/or asthenozoospermia. An association between zinc concentration and semen analysis remained unclear. This study was cross-sectional and retrospective, however, this is a largest investigation of the zinc concentration during reproductive life span in Japan. Further accumulation of cases are required to further examine the potential relationship between zinc concentration and semen quality.

P-766 Birth outcomes in Anti-centromere antibody (ACA) -positive patients treated with ART

Study question

Does the presence of the ACA have any effect on pregnancy and birth?

Summary answer

Presence of ACA did not have an impact on pregnancy and birth parameters measured.

What is known already

We have previously shown that patients with high levels of anti-centromere antibody (ACA), one of the anti-nuclear antibodies (ANA), frequently have dispersion of chromosomes in the cytoplasm. Additionally, we reported that it was characterized by a low oocyte maturation rate as observed at ovum pick up, high multiple pronuclear formation after fertilization and a low pregnancy rate after embryo transfer. Thus, the effect of ACA on fertility is clear, but the impact following pregnancy establishment has not yet been reported. Therefore, we followed up on birth outcomes in ACA-positive patients treated with ART.

Study design, size, duration

3379 patients who underwent ANA testing followed by embryo transfer between January 2014 and February 2020 and who gave birth including the results of single births with no abnormal or missing values for week and birth weight were analyzed. The subjects were classified into three groups: ANA-negative (without ACA or any other ANA), ACA-positive (with only ACA) and ANA-positive (with ANA but not ACA).

Participants/materials, setting, methods

We compared mean birth weight (full term), low weight birth infant (less than 2,500g) rate, sex ratio, congenital anomaly rate, preterm birth rate, cesarean section rate, and mean apgar score (AP) in the three groups. We treated “don't know” and “blank” for items other than week and birth weight as non-responses and missing values.

Main results and the role of chance

Of the 3379 cases for analysis, the group numbers were ANA-: 2465, ACA+: 21, ANA+: 893. The mean birth weights were 3099.6g, 3055.3g and 3088.5g respectively. In the 3 groups the rate of low birth weight infants were 8.7% (215/2465), 9.5% (2/21) and 9.2% (82/893), the sex ratio (male/female)-1.03 (1246/1212), 0.62 (8/13) and 0.93 (429/ 460), congenital anomaly rate 2.7% (67/2465), 4.8% (1/21), 3.2% (29/893), preterm birth rate 7.4% (86/2465), 4.8% (1/12), 6.7% (60/893), cesarean rate 40.0% (979/2448), 42.9% (9/21), 41.3% (367/888), and mean AP was 8.3, 8.2, and 8.3 respectively. There was no significant difference between the three groups in any of the measured items.

Limitations, reasons for caution

This study was conducted at a single institution, and only the results of those who responded to the birth survey questionnaire were analyzed. Because of the small number of patients in the ACA group, continued follow-up is considered necessary.

Wider implications of the findings

It was shown that ACA strongly affects maternal fertility, but seems to have no effect on birth parameters. However we will continue to follow up with further long-term prognostic studies.

Trial registration number

not applicable

P-048 Fertilization rate and embryonic development after intracytoplasmic sperm injection (ICSI) using a microfluidic sperm selection device without centrifugation

Study question

Can the use of a microfluidic sperm selection device without centrifugation simplify the procedure without affecting fertilization rates and embryonic development after ICSI?

Summary answer

The microfluidic device can be used to select sperm in a simple procedure without reducing the fertilization or embryo development rate.

What is known already

In human ART, it is essential to process the semen and adjust the sperm sample according to the intended purpose, rather than using raw semen. Current sperm preparation methods at most IVF clinics include the density gradient centrifugation method, which utilizes the difference in density between the maturation stages of sperm, followed by washing using centrifugation. However, these methods require a lot of steps and the procedure is complicated. Recently, several non-centrifugal sperm processing devices have become available. One of them is a simple sperm conditioning method using a microfluidic device.

Study design, size, duration

This was a prospective study using sibling oocytes including 20 ART patients treated with 24 cycles and where there were 320 zygotes after ICSI. The duration of the study was 8 months (May 2020 to December 2020).

Participants/materials, setting, methods

For sperm preparation without centrifugation, a microfluidic device “ZyMōtⓇ Multi 850μL” was used. According to the labelled use, 850μL of semen was required with “ZyMōtⓇ” device (ZyMōt group), and the rest of the semen was processed according to routine laboratory procedure by monolayer density gradient centrifugation and washing by centrifugation (DGC group). Oocytes from the same patient were randomly divided into 2 batches and ICSI was performed using sperm treated with each method.

Main results and the role of chance

The 2PN formation rate in the ZyMōt group was 84.5% (142/168), which was not significantly different from 82.9% (126/152) in the DGC group. There was also no significant difference in 1PN formation rate (3.0% vs. 3.3%), multi PN formation rate (3.6% vs. 3.3%) and the non-fertilization rate (8.3% vs. 10.5%). The good quality embryo rate at Day 3 was 25.0% (31/124) in the ZyMōt group and 24.5% (27/110) in the DGC group, with no significant difference. The Day 5 blastocyst rate was 37.9% (47/124) in the ZyMōt group and 36.7% (40/109) in the DGC group, and the cumulative blastocyst rates by Day 7 were 54.0% (67/124) and 57.8% (63/109), respectively, with no significant difference.

Limitations, reasons for caution

This study was limited to samples with a motile sperm concentration of more over 1.0 × 106 in raw semen.

Wider implications of the findings

These results demonstrated that sperm processing using the microfluidic device without centrifugation does not affect the fertilization or blastocyst development rate after ICSI and that the sperm processing procedure can be simplified by using this device.

Trial registration number

not applicable

Asynchronous division at 4–8-cell stage of preimplantation embryos affects live birth through ICM/TE differentiation

To improve the performance of assisted reproductive technology, it is necessary to find an indicator that can identify and select embryos that will be born or be aborted. We searched for indicators of embryo selection by comparing born/abort mouse embryos. We found that asynchronous embryos during the 4–8-cell stage were predisposed to be aborted. In asynchronous mouse embryos, the nuclear translocation of YAP1 in some blastomeres and compaction were delayed, and the number of ICMs was reduced. Hence, it is possible that asynchronous embryos have abnormal differentiation. When the synchrony of human embryos was observed, it was confirmed that embryos that did not reach clinical pregnancy had asynchrony as in mice. This could make synchrony a universal indicator common to all animal species.

Search for morphological indicators that predict implantation by principal component analysis using images of blastocyst

Background

Although the current evaluation of human blastocysts is based on the Gardner criteria, there may be other notable parameters. The purpose of our study was to clarify whether the morphology of blastocysts has notable indicators other than the Gardner criteria.

Methods

To find such indicators, we compared blastocysts that showed elevated human chorionic gonadotropin (hCG) levels after transplantation (hCG-positive group; n = 129) and those that did not (hCG-negative group; n = 105) using principal component analysis of pixel brightness of the images.

Results

The comparison revealed that the hCG-positive group had grainy morphology and the hCG-negative group had non-grainy morphology. Classification of the blastocysts by this indicator did not make a difference in Gardner score. Interestingly, all embryos with ≥20% fragmentation were non-grainy. The visual classification based on this analysis was significantly more accurate than the prediction of implantation using the Gardner score ≥3BB. As graininess can be used in combination with the Gardner score, this indicator will enhance current reproductive technologies.

Secondary male infertility: the importance of the urological assessment for couples who desire children in later life

Amongst 942 out-patients who consulted our male infertility division between 2016 to 2020, 85 (9.0%) patients suffered from secondary infertility. Of these, in 59 (69.4%) subjects, the first pregnancy was achieved by natural conception. 81 subjects were evaluated for semen quality except for two subjects who at the time were undergoing cancer treatment and another of two ejaculatory dysfunction (EjD). Semen analysis revealed 16 subjects (19.8%) were azoospermic, whereas 9 (11.1%) were cryptozoospermic at median three years of infertility. Left varicocelectomy had been undertaken in a total of 17 oligoasthenozoospermic and cryptozoospermic cases in order to improve semen quality. For achieving natural pregnancy, microscopic vasoepididymostomy was performed in 3 subjects of obstructive azoospemia and patency was achieved in two of three. 11 azoospermic subjects and two of the EjD underwent sperm retrieval surgery for intracytoplasmic sperm injection (ICSI). Motile sperm recovery was obtained by microscopic epididymal sperm aspiration (5/5=100%), microscopic testicular sperm extraction (micro-TESE, 2/6=33.3%), and retrograde vasal sperm aspiration (2/2=100%). Natural pregnancy was obtained in two subjects following varicocelectomy, and in one following vasoepididymostomy. Seven pregnancies were achieved by ICSI using cryopreserved sperm and surgically retrieved sperm. Even if the first pregnancy occurred naturally, 30.9% subjects showed azoospermia or cryptozoospermia at median duration of three years. We would like to emphasize that earlier urological assessment especially semen analysis is necessary if pregnancy later in life is desired.

Oocyte cytoplasmic diameter of ≥130 μm can be used to determine human giant oocytes

OBJECTIVE

To determine if a cytoplasmic diameter of ≥130 μm can help identify human giant oocytes (GOs) in clinical practice and confirm the presence of genetic abnormalities in GOs by assessing the spindle length and centromere numbers.

DESIGN

Case-control study.

SETTING

Private in vitro fertilization clinic.

PATIENT(S)

The subjects were women aged 20-49 years who underwent oocyte retrieval after ovarian stimulation from January 2014 to December 2020.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The oocyte diameter was measured; immunofluorescent staining was performed to assess the spindle diameter and centromere numbers.

RESULT(S)

Among the 254,337 oocytes examined, 561 (0.22%) had a diameter of ≥130 μm. The mean diameter ranges in the normal-sized metaphase II (MII) oocytes (MII group) and GO group were 103.0-119.0 and 132.3-175.9 μm. Spindle size could be measured in 6 GOs with 1 spindle (GO1), 10 GOs with 2 spindles (GO2), and 16 MII groups. The equatorial plane and pole-to-pole distance in the GO1 were significantly longer than in the GO2 and MII groups. The median numbers of centromeres were 86 in GOs with 1 spindle and 42 in each spindle for GOs with 2 spindles among 11 GO1s and 5 GO2s.

CONCLUSION(S)

This study is the first to define GOs as oocytes with a diameter of ≥130 μm and is a large-scale study surveying the incidence of GO. It is also the first study to analyze and elucidate the relationship between spindle numbers within the cytoplasm of GOs and spindle size and centromeres.

P–156 Automatic pronuclear detection based on deep learning technology has clinical utility

Study question

Does the performance of an automatic pronuclear detection system based on deep learning technology have clinical utility?

Summary answer

Output results for 2PN detection using the automatic system powered by deep learning technology has clinical utility.

What is known already

In order to establish a more objective embryo evaluation system, we have been developing an automatic pronuclear detection system that utilizes deep learning technology based on Time- Lapse (TL) images. We have previously reported that the accuracy of pronuclei detection was improved by introducing an analysis method using 11 slices in the Z axis. In this study, we evaluated the potential clinical practicality of the automatic pronuclear detection system.

Study design, size, duration

Embryos clinically evaluated between May 2018 and December 2019 by embryologists were chosen for this study. We prepared for analysis TL videos of 995 embryos that had been evaluated as having 0, 1, 2, and 3PN.

Participants/materials, setting, methods

Part1:We compared the outputs of the automatic pronuclear detection system with these embryologists(three junior embryologists (1a), three intermediate embryologists (1b),and three senior embryologists (1c)) who had judged the pronuclei number from TL videos from 40 embryos each having 0,1,2,and 3PN.

Part2:The automatic pronuclear detection system determined the pronuclei number from the TL videos of 955 embryos scored as either 1,2,and 3PN,(different from those used in Part1),and the detection rate for 2PN was calculated.

Main results and the role of chance

Part1: The sensitivities for embryologist groups 1a),1b),1c) and the automatic pronuclear detection system were 80.0%,100%,100%,100% for 2PN, 60.0%,83.3%,86.7%,100% for 0PN, 46.7%,80.0%,86.7%,10.0% for 1PN, and 73.3%,96.7%,96.7%,10.0% for 3PN.

Part2: The precision for 2PN by the automatic pronuclear detection system was 99%.

Limitations, reasons for caution

In order to further improve the performance of the automatic pronuclear detection system, further adjustment of the algorithm and more training images will be utilised.

Wider implications of the findings: The detection of 2PN by the automatic pronuclear detection system was highly reliable, and the performance of the system was comparable to that of embryologists. These first results are reassuring and support the clinical use of the system as a further aid for embryologists, in routine laboratory practice.

Trial registration number

‘not applicable’

P–784 Neonatal follow-up of babies born derived from mono-pronuclear zygotes

Study question

Are the neonatal outcomes normal of babies derived from the transfer of blastocysts derived from mono-pronuclear(1PN) zygotes?

Summary answer

There was no effect on growth or increase in congenital anomalies up to 18-months in babies of 1PN-derived births.

What is known already

1PN zygotes are observed in ART, albeit at a low rate. We have previously reported that 80.7% of 1PN zygotes derived from IVF or ICSI had a biparental chromosome using Live Cell imaging techniques, and some of these developed to the blastocyst stage (Tokoro et al. ASRM 2013). Furthermore, we have reported that these blastocysts can result in a viable pregnancy and healthy live birth (Tsuji et al. ASRM2020). However, there is some uncertainty about the developmental mechanism of 1PN zygotes, and there is no clear consensus on their clinical utility.

Study design, size, duration

This was a retrospective study which included 55 cases where there was a live birth after single embryo transfer of a blastocyst derived from 1PN zygote. The incidence of birth defects, birth weight was recorded as well as a physical development survey of 25 children who responded to the 18-months follow-up survey. The time period was 72 months (January 2013 to December 2018).

Participants/materials, setting, methods

Patients seeking fertility treatment at an established private IVF clinic. We compared the birth weight, birth after18-months height and weight of children born to 1PN zygotes with data from a control, 2PN group. Statistical significance was determined using the t-test (level of P < 0.05).

Main results and the role of chance

The incidence of birth defects in 1PN embryo-derived infants was 1.8% (1/55). The average birth weight of boys in the 1PN group was 3105.6+/–360.3g, which was not significantly different from 3041.0+/–443.3 g in the 2PN group. In girls, the average birth weight was 3085.7+/–454.9 g in the 1PN group, which was not significantly different from the 2PN group (2938.9+/–311.5 g). The average height at 18-months, was 81.6+/–2.5 cm vs 80.5+/–3.4 cm for boys; 79.0+/–1.8 cm vs 79.0+/–3.4 cm for girls in the 1PN and 2PN groups, respectively. The average body weights of the 1PN and 2PN groups were 11.1+/–1.1 kg vs 10.7+/–1.1 kg for boys; 9.7+/–0.9 kg vs 10.1+/–1.0 kg for girls, respectively. There was no significant difference in average height and weight up-to the 18-months follow-up survey.

Limitations, reasons for caution

The incidence of 1PN derived births is low and the study was limited to cases of single blastocyst embryo transfer.

Wider implications of the findings: The incidence of congenital anomalies in Japan was around 1.7 to 2%, and the incidence was similar in the 1PN. There was no difference in the birth weight and 18-months follow-up survey of the 1PN compared with the 2PN. We have demonstrated that there is clinical utility of 1PN embryo.

Trial registration number

Not applicable

P–155 Oocyte recovery 39 hours (from 39h to 41h) after administration of follicular maturation trigger does not affect clinical results

Study question

What is the clinical outcome of oocytes recovered after 39 hours from ovulation inducing drug administration?

Summary answer

Oocytes obtained after 39 hours from follicular maturation triggering are equally viable to those obtained at the standard time of 36 hrs.

What is known already

In the clinical setting of ART, ovum pick-up (OPU) is generally performed around 36 hours after the administration of ovulation inducing drugs (OID). However, there are cases where OPU cannot be performed at this time often due to long operating lists. As the time elapsed between the administration of ovulation inducing drugs and OPU becomes longer, there is a concern about time-related oocyte aging. Nevertheless, there are few reports of clinical results of OPU after 36 hours from OID.

Study design, size, duration

We conducted a review of 1187 cycles and 1951 patients in which OPU and embryo transfer was performed in 2017–2018. All cycles underwent a ‘freeze-all’ of embryos and the transfer cycle was in the thawed embryo transfer cycle for all cases.

Participants/materials, setting, methods

The time from the administration of OID to the end of OPU was divided into 36h group and over 39h group and the MII and normal fertilization rate of oocytes obtained from OPU after ovarian stimulation were compared. After confirmation of fertilization, the D3 good-quality embryo and the D5 and 6 good-quality blastocyst rates of embryos that continued to be cultured and the pregnancy and miscarriage rates of cleavage-stage embryos and blastocyst transfers were compared.

Main results and the role of chance

The MII rate in the 36h and >39h groups was 78.1% vs. 80.0%, and the normal fertilization rate was 77.9% vs. 78.1% (ICSI) and 65.4% vs. 67.6% (Conventional-IVF). The D3 good-quality embryo rate (good-quality embryos are embryos with less than 5% fragmentation in 7–9 cells and compaction with more than 50% adhesion between split spheres) was 21.8% vs. 25.3%, the D5 good-quality blastocyst rate (at least 3BB according to Gardner classification) was 33.6% vs. 40.1%, and the D6 good-quality blastocyst rate was 31.1% vs. 37.5%, all of which were not significantly different. The pregnancy rate for cleavage-stage embryo transfer was 26.6% vs. 6.7%, and the miscarriage rate was 25.3% vs. 42.9%, both of which were not significantly different. The pregnancy rate for blastocyst transfer was 45.4% vs. 50.0%, and the miscarriage rate was 22.2% vs. 20.0%, both of which were not significantly different. (The significance difference test was a χ-square test)

Limitations, reasons for caution

The study was a retrospective study.

Wider implications of the findings: Even if OPU is conducted after 36h of the administration of OID, to the extreme range of 39h–41h, oocyte aging does not seem apparent and pregnancy outcomes are similar to the standard time interval of 36 hours.

Trial registration number

‘not applicable’

P–354 Analysis of pregnancy and miscarriage rates in anti-centromere antibodies (ACA)-positive patients treated with ART

Study question

Do ACA have an effect on pregnancy and miscarriage rates of human embryos?

Summary answer

The present results suggest that in ACA-positive cases, the pregnancy rate per transfer was significantly lower, although the miscarriage rate was not affected.

What is known already

We have previously shown that patients with high levels of anti-centromere antibody (ACA), (one of the anti-nuclear antibodies (ANA)), frequently have dispersal of the female chromosomes in the cytoplasm. Additionally, we reported that the clinical outcome was characterized by a low oocyte maturation rate following ovum pick up and high multiple pronuclear formation rate after fertilization. However, the post-implantation course of embryos with ACA-positive cases has not yet been reported. Therefore, in this study, we analyzed the pregnancy and miscarriage rates in ACA-positive patients treated with Assisted Reproductive Technologies (ART).

Study design, size, duration

6581 patients who underwent embryo transfer after antinuclear antibody testing between January 2014 and February 2020 were included in the analysis.

Participants/materials, setting, methods

The subjects were classified into three groups: ANA-negative (without ACA or any other ANA), ACA-positive (with only ACA) and ANA-positive (with ANA but not ACA). The cycle in which the gestational sac was confirmed was considered a positive pregnancy. The pregnancy and miscarriage rates were compared among the groups using “Ryan Test” for statistical analysis.

Main results and the role of chance

Of the 6581 eligible cases, the incidence of antinuclear antibody were 71.3% (4695/6581; ANA-negative), 0.9% (61/6581; ACA-positive) and 27.7% (1825/6581; ANA-positive). The pregnancy rates based on the total number of embryo transfer cycles for each were ANA-negative: 31.5% (5283/16792), ACA-positive: 17.6% (41/233), and ANA-positive: 32.4% (1891/5833). The pregnancy rates were significantly lower in the ACA-positive group than in the other groups. The miscarriage rate was 29.4% (1553/5283) in ANA-negative, 31.7% (13/41) in ACA-positive, and 28.0% (529/1891) in ANA-positive, with no significant difference between the three groups.

Limitations, reasons for caution

Retrospective analysis

Wider implications of the findings: ACA-positive patients may benefit from a treatment strategy to increase the absolute number of oocytes by obtained in order to increase the chances of normal fertilization and attainment of implantation.

Trial registration number

none

Gonadotropin levels at the start of ovarian stimulation predict normal fertilization after hCG re-trigger in GnRH antagonist cycles

PURPOSE

To assess the appropriateness of human chorionic gonadotropin (hCG) re-trigger in poor responders to gonadotropin-releasing hormone agonist (GnRHa) trigger in controlled ovarian stimulation (COS) cycles.

METHODS

The 2251 cycles in 2251 patients triggered with GnRHa for oocyte stimulation, with or without requiring hCG re-trigger between 2013 and 2018, were retrospectively analyzed to compare gonadotropin levels at the start of COS and the rate of normal fertilization between the re-trigger and non-re-trigger group. Furthermore, patients in the re-trigger group were stratified by the rate of normal fertilization (good: ≥60% or poor: <60%) to compare patient demographics, hormone profiles, and clinical outcome between the subgroups.

RESULTS

In the re-trigger group, FSH and LH levels at the start of COS were significantly lower in the good fertilization group than in the poor fertilization group (P < .01). Receiver operating characteristic curves identified cutoff values of the FSH and LH levels of 1.30 and 0.35 mIU/mL, respectively, for predicting ≥60% normal fertilization.

CONCLUSION

Gonadotropin levels at the start of COS are predictors of response to GnRHa trigger and hCG re-trigger necessity, and may serve as indicators to help clinicians appropriately choose hCG re-trigger rather than abandoning the cycles or continuing the first oocyte aspiration attempt.

Microsurgical seminal reconstruction; our experiences in a single institute

We assessed the contribution of microsurgical seminal reconstruction to achieving natural conception in conjunction with advanced assisted reproductive technologies. Ninety obstructive azoospermic subjects who underwent microsurgical seminal reconstruction were evaluated. Vasovasostomy (VV) was undertaken in 45 subjects whereas vasoepididymostomy (VE) in 45, respectively. VV was performed by employing a two microlayer anastomotic technique, whilst VE was undertaken using double needle longitudinal vaspepididymostomy (LIVE). Patency was achieved in 41 VV (91.1%), and 25 VE (55.6%) cases. In cases where patency was achieved, pregnancy and healthy delivery were recorded following natural intercourse in 7/41 (17.0%) VV, and in 7/25 (28.0%) VE cases. Where patency was not achieved, the use of cryopreserved sperm for intracytoplasmic sperm injection (ICSI), resulted in a healthy delivery in 4/4 (100%) VV and 14/21 (66.6%) in VE subjects. Although natural pregnancy was achieved only in a limited number of subjects treated (14/90; 15.6%), sperm harvested during surgery and cryopreserved for future ICSI use proved valuable, doubling the overall delivery rate (32/90; 36.6%). Surgical intervention is considered to be a useful technique in order to allow the possibility of a natural conception and by harvesting sperm at the same time contributes to the cost-effectiveness.

Development of an automated two pronuclei detection system on time-lapse embryo images using deep learning techniques

PURPOSE

To establish an automated pronuclei determination system by analysis using deep learning technology which is able to effectively learn with limited amount of supervised data.

METHODS

An algorithm was developed by explicitly incorporating human observation where the outline around pronuclei is being observed in determining the number of pronuclei. Supervised data were selected from the time-lapse images of 300 pronuclear stage embryos per class (total 900 embryos) clearly classified by embryologists as 0PN, 1PN, and 2PN. One-hundred embryos per class (a total of 300 embryos) were used for verification data. The verification data were evaluated for the performance of detection in the number of pronuclei by regarding the results consistent with the judgment of the embryologists as correct answers.

RESULTS

The sensitivity rates of 0PN, 1PN, and 2PN were 99%, 82%, and 99%, respectively, and the overlapping 2PN being difficult to determine by microscopic observation alone could also be appropriately assessed.

CONCLUSIONS

This study enabled the establishment of the automated pronuclei determination system with the precision almost equivalent to highly skilled embryologists.

Chromosome segregation error during early cleavage in mouse pre-implantation embryo does not necessarily cause developmental failure after blastocyst stage

In the pre-implantation embryo, aneuploidy resulting from chromosome segregation error is considered responsible for pregnancy loss. However, only a few studies have examined the relationship between chromosome segregation errors during early cleavage and development. Here, we evaluated this relationship by live-cell imaging using the histone H2B-mCherry probe and subsequent single blastocyst transfer using mouse embryos obtained by in vitro fertilization. We showed that some embryos exhibiting early chromosomal segregation error and formation of micronuclei retained their developmental potential; however, the error affected the blastocyst/arrest ratio. Further, single-cell sequencing after live-cell imaging revealed that all embryos exhibiting micronuclei formation during 1^st mitosis showed aneuploidy at the 2-cell stage. These results suggest that early chromosome segregation error causing micronuclei formation affects ploidy and development to blastocyst but does not necessarily cause developmental failure after the blastocyst stage. Our result suggests the importance of the selection of embryos that have reached blastocysts.

Performance of anti-Müllerian hormone (AMH) levels measured by Beckman Coulter Access AMH assay to predict oocyte yield following controlled ovarian stimulation for in vitro fertilization

PURPOSE

We evaluated the performance of anti-Müllerian hormone (AMH) measured by the Beckman Coulter fully automated Access assay to predict oocyte yield following controlled ovarian stimulation (COS) for in vitro fertilization (IVF).

METHODS

The correlation between the Access assay and the pre-mixing method with Generation II ELISA assay (Gen II pre-mix assay) was assessed using 230 blood samples. The relationship of AMH level measured by the Access assay and the actual number of oocytes retrieved following COS was assessed using 3296 IVF cycles. The performances of AMH, follicle stimulating hormone (FSH), and estradiol (E2) in predicting the responses to COS were also evaluated by constructing receiver operating characteristic (ROC) curves.

RESULTS

The AMH levels measured just before oocyte retrieval by the Access assay and the number of oocytes retrieved following COS showed a good correlation with R = 0.655. The ROC analysis revealed that the sensitivity of AMH was comparable with or lower than that of E2 but higher than that of FSH.

CONCLUSIONS

With the improved Access AMH assays, AMH was as sensitive as E2 and could become an accurate marker of ovarian response to COS in more than 3000 Japanese IVF patients.

Clinical utility of chlormadinone acetate (Lutoral™) in frozen-thawed embryo transfer with hormone replacement

PURPOSE

The clinical utility of chlormadinone acetate tablets (Lutoral™), an orally active progestin which has been available since June 2007, was compared to an in-house vaginal suppository formulation of progesterone used between 2006 and 2007 for assisted reproductive technology (ART).

METHODS

We retrospectively evaluated the efficacy and safety of chlormadinone acetate by comparing the pregnancy rates and the incidences of birth defects and hypospadias in frozen-thawed embryo transfer cycles using the in-house vaginal progesterone and those using chlormadinone acetate for luteal phase support.

RESULTS

The pregnancy rates in the frozen-thawed embryo transfer cycles were 31.2% (259/831) with vaginal progesterone for luteal phase support and 31.6% (4228/13 381) with chlormadinone acetate (no significant difference). In the cycles resulting in live birth following administration of chlormadinone acetate between July 2007 and December 2015, the incidence of birth defects was 2.8% (80/2893), and the incidence of hypospadias was 0.03% (1/2893).

CONCLUSIONS

These results indicate that the pregnancy rate following frozen-thawed embryo transfer using chlormadinone acetate for luteal phase support was comparable with that using vaginal progesterone, with no increased risk of birth defects, including hypospadias, which has been a concern following the use of progestins.

Long-term outcomes of freeze-all strategy: A retrospective analysis from a single ART center in Japan

PURPOSE

To demonstrate the benefits of the freeze-all strategy for in vitro fertilization treatment based on retrospective analyses.

METHODS

Post-thaw embryo survival rates of slow-frozen embryos in 294 cycles and vitrified embryos in 12 195 cycles were assessed. Progesterone (P4) and estradiol (E2) levels per mature oocyte by age category were assessed in 9081 cycles and pregnancy rates with fresh embryo transfer and frozen-thawed embryo transfer by P4 level were assessed in 1535 cycles.

RESULTS

The survival rates of frozen-thawed embryos were 92.5% with slow freezing and 99.1% with vitrification. P4 levels on the day of human chorionic gonadotropin (hCG) injection showed a trend toward an increase with age. The pregnancy rate per mature oocyte with fresh embryo transfer decreased dependently upon P4 level, while that with frozen-thawed embryo transfer was not affected by P4 level. The pregnancy rates with frozen-thawed embryo transfer were higher than those with fresh embryo transfer in patients aged 42 years or younger.

CONCLUSIONS

The freeze-all strategy is a valuable treatment option which allows the separation of an embryo transfer cycle from an oocyte retrieval cycle, especially for patients with high P4 levels at oocyte retrieval and patients of advanced maternal age.

Superior clinical pregnancy rates after microsurgical epididymal sperm aspiration

Purpose

To assess normal fertilization, clinical pregnancy, and live birth rates after the use of microscopic epididymal sperm aspiration (MESA).

Methods

One-hundred-and-sixty azoospermic participants who underwent MESA were evaluated. The MESA was performed by using a micropuncture method with a micropipette. In cases in which motile sperm were not obtained after the MESA, conventional or micro-testicular sperm extraction (TESE) was completed.

Results

Adequate motile sperm were retrieved in 71 participants by using MESA and in 59 out of 89 participants by using TESE. Of the total number of patients, 123 underwent intracytoplasmic sperm injection. After MESA, the normal fertilization rate was 73.5% and the clinical pregnancy rate per case was 95.7%. Healthy deliveries resulted after MESA in 65 (92.9%) cases and after TESE in 38 (71.7%) cases.

Conclusion

The MESA specimen collection does not have any special requirements, such as mincing tissue disposition. The MESA also can reduce the amount of laboratory work that is needed for cryopreservation. In the authors' experience, MESA is a beneficial procedure and should be given priority over TESE.

A Simple Method for Transportation of Mouse Embryos Using Microtubes and a Warm Box

Generally, transportation of preimplantation embryos without freezing requires incubators that can maintain an optimal culture environment with a suitable gas phase, temperature, and humidity. Such incubators are expensive to transport. We reported previously that normal offspring were obtained when the gas phase and temperature could be maintained during transportation. However, that system used plastic dishes for embryo culture and is unsuitable for long-distance transport of live embryos. Here, we developed a simple low-cost embryo transportation system. Instead of plastic dishes, several types of microtubes—usually used for molecular analysis—were tested for embryo culture. When they were washed and attached to a gas-permeable film, the rate of embryo development from the 1-cell to blastocyst stage was more than 90%. The quality of these blastocysts and the rate of full-term development after embryo transfer to recipient female mice were similar to those of a dish-cultured control group. Next, we developed a small warm box powered by a battery instead of mains power, which could maintain an optimal temperature for embryo development during transport. When 1-cell embryos derived from BDF1, C57BL/6, C3H/He and ICR mouse strains were transported by a parcel-delivery service over 3 days using microtubes and the box, they developed to blastocysts with rates similar to controls. After the embryos had been transferred into recipient female mice, healthy offspring were obtained without any losses except for the C3H/He strain. Thus, transport of mouse embryos is possible using this very simple method, which might prove useful in the field of reproductive medicine.