Association between morphologic grading and implantation rate of Euploid blastocyst

Thyroid-stimulating hormone levels are associated with estradiol levels and impact reproductive outcomes in preconceptionally euthyroid women undergoing their first IVF/ICSI cycles

PURPOSE

Controlled ovarian hyperstimulation (COH) has been reported to affect thyroid function; however, the impact of thyroid-stimulating hormone (TSH) levels during COH on embryo development and early reproductive outcomes has largely not been determined. Therefore, the aim of the present study was to investigate whether TSH levels are associated with COH and impact early reproductive outcomes in preconceptionally euthyroid women.

METHODS

This was a prospective cohort study. A total of 338 euthyroid women who underwent their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment using the gonadotropin releasing hormone agonist (GnRH-a) protocol were included. Samples were collected at different representative time points for TSH and estradiol measurements.

RESULTS

TSH levels significantly increased with the administration of Gn and maintained this tendency until the trigger day. Basal TSH levels increased along with basal estradiol levels and remained stable when estradiol levels were higher than 150 pmol/L. On the trigger day, TSH levels changed with increasing estradiol levels in the high-normal basal TSH group but not in the low TSH group. TSH did not impact clinical pregnancy or early pregnancy loss after adjusting for age, stage or number of embryos.

CONCLUSION(S)

Serum TSH levels change significantly during COH and are associated with significant changes in estradiol levels. However, euthyroid women with high-normal TSH levels showed similar development potential for inseminated embryos and early reproductive outcomes compared to those with low TSH levels.

Effect of development speed and quality of blastocyst on singleton birthweight in single frozen-thawed blastocyst transfer cycles

Background

Assisted reproductive technology (ART) has revolutionized infertility treatment, leading to a surge in ART-conceived children. Despite its success, ART-born offspring face higher risks of preterm birth (PTB), low birth weight (LBW), and small for gestational age (SGA). The mechanisms behind these outcomes remain unclear, partly attributed to multiple embryo transfers. Recent advancements advocate single blastocyst transfers for improved outcomes. However, the influence of blastocyst quality and development speed on neonatal outcomes is underexplored.

Objective

This study investigated whether blastocyst development speed and quality affect singleton birthweight when the blastocyst is selected for single frozen-thawed blastocyst transfer (FBT).

Methods

Data from patients who performed an FBT cycle at our center from July 2011 to June 2021 were collected and analyzed. Based on the inclusion and exclusion criteria, 420 single FBT cycles were assessed. The women were divided into four groups, Group A (day 5, good-quality blastocysts), Group B (day 5, non-good-quality blastocysts), Group C (day 6, good-quality blastocysts), and Group D (day 6, non-good-quality blastocysts) according to the developmental speed and quality of the transferred blastocyst.

Results

The birthweight was relatively the highest in Group A, which developed rapidly and transferred good quality blastocysts. However, no significant difference existed among the groups (P>0.05). The prevalence of premature birth (PTB), low birth weight (LBW), very low birth weight (VLBW), or high birth weight (HBW) was similar among the four groups (P > 0.05). No correlation existed between birth weight and blastocyst development speed or quality after adjusting for possible confounders (P > 0.05 respectively). However, the difference in the proportion of males born among the four groups was significant, especially in Group D, which was significantly lower than that in Group A (adjusted odds ratio = 0.461, 95% confidence interval: 0.230-0.921, P < 0.05).

Conclusions

This retrospective cohort study suggests that the combined effect of blastocyst development speed and quality on neonatal birthweight is insignificant. The transfer of slow-growing, non-good-quality blastocysts increases the chance of a female baby being born.

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.

Comparison of reproductive outcomes in subclinical hypothyroidism women with high-normal versus low-normal thyroid-stimulating hormone levels after treatment with levothyroxine

OBJECTIVE

Reproductive outcomes in euthyroid women with high-normal thyroid-stimulating hormone (TSH) levels are comparable to those in euthyroid women with low TSH levels; however, few studies have investigated whether strictly controlled TSH levels after levothyroxine (LT4) treatment impair reproductive outcomes in infertile women with subclinical hypothyroidism (SCH). This study aimed to investigate the impact of high-normal versus low-normal TSH levels on reproductive outcomes in women undergoing their first in vitro fertilisation and embryo transfer (IVF-ET) cycle.

DESIGN

This was a retrospective cohort study. Patients were divided into low-normal (TSH < 2.5 mIU/L, and ≥0.27 mIU/L) and high-normal (TSH ≥ 2.5 mIU/L, and <4.2 mIU/L) groups based on TSH levels after LT4 treatment. TSH levels after LT4 treatment and before ovarian stimulation were recorded. Reproductive outcomes were compared between the low-normal and high-normal TSH groups and between the euthyroid and LT4-treated groups.

RESULTS

A total of 6002 women, 548 of whom were LT4-treated women, were finally included in this study. Among the LT4-treated women, 129 women had low-normal TSH levels, and 167 women had high-normal TSH levels. The clinical pregnancy rate, miscarriage rate, and live birth rate were comparable between the low-normal and high-normal groups (all p > .05). When adjusted by age, anti-Mullerian hormone (AMH) levels, infertility duration, transferred embryos, and dose and duration of LT4 treatment, high-normal TSH levels neither significantly decreased miscarriage (adjusted odds ratio [aOR] = 2.27, 95% confidence interval [CI] = 0.77-6.69, p = .14) nor increased clinical pregnancy (aOR = 1.15, 95% CI = 0.70-1.89, p = .57 or live birth (aOR = 0.97, 95% CI = 0.60-1.59, p = .92). Similar obstetric outcomes were observed between the low-normal and high-normal TSH groups after LT4 treatment and between the euthyroid and LT4-treated groups (all p ≥ .05).

CONCLUSIONS

High-normal TSH levels did not have adverse effects on clinical and obstetric outcomes when compared with low-normal TSH levels after LT4 treatment. However, whether it is appropriate to set 2.5 mIU/L as the goal of treatment before IVF/ICSI remains to be determined in further well-designed studies.

No advantage of single day 6 good-quality blastocyst transfer versus single day 5 poor-quality blastocyst transfer in frozen-thawed cycles stratified by age: a retrospective study

BACKGROUND

Blastocyst developmental speed, morphological grading and patient age are associated with pregnancy outcomes of frozen-thawed cycles. This study aimed to compare the clinical and neonatal outcomes between poor-quality D5 blastocysts and good-quality D6 blastocysts stratified by patient age.

METHODS

A total of 1,623 cycles were divided into two groups: group A (n = 723) received one D5 poor-quality blastocyst; group B (n = 900) received one D6 good-quality blastocyst. Pregnancy and neonatal outcomes were compared among the four groups stratified by 35 years of age.

RESULTS

When patients were in the same age group, there was no significant difference in terms of age, body mass index, infertility duration, infertility type, fertilization method, proportion of endometrial preparation protocols, and endometrial thickness between D5 poor-quality and D6 high-quality blastocysts groups. Live birth rate of D5 poor-quality blastocysts was higher than that of D6 high-quality blastocysts for patients aged < 35 years (35.48% vs. 31.13%, p > 0.05), but there was no statistical difference. The same trend was showed for patients aged ≥ 35 years (29.09% vs. 21.28%, p > 0.05). Moreover, when patients were in the same age category, there was no significant difference in terms of gestational age, birth weight, birth height, and rates of preterm birth, low birth weight, and very low birth weight between groups A and B.

CONCLUSIONS

The preferential selection of poor-quality D5 blastocysts for transfer compared to high-quality D6 blastocysts is recommended, especially for advanced age patients. Single good-quality D6 blastocyst transfer can be considered for the acceptable live birth rate.

Does the risk of embryo abnormality increase in PCOS women? A secondary analysis of a multi-center randomized controlled trial

CONTEXT

Some studies reported the early miscarriage rate was higher in PCOS women. However, whether the risk of embryo abnormalities increases in PCOS women is lack of evidence.

OBJECTIVE

To evaluate the association between polycystic ovarian syndrome (PCOS) and embryo ploidy.

DESIGN

A secondary analysis of multi-center randomized controlled trial which was conducted from July 2017 to June 2018. The original intent was to identify whether preimplantation genetic test for aneuploidy (PGT-A) improves the live birth rate as compared with in-vitro fertilization (IVF).

SETTING

14 reproductive centers.

PATIENTS

190 patients diagnosed with PCOS and 1:1 age-matched non-PCOS patients were chosen from PGT-A group. A total of 380 patients with 1118 embryos were included in our study.

INTERVENTIONS

Women diagnosed with PCOS.

MAIN OUTCOME MEASURES

Embryonic aneuploidy and embryonic mosaic.

RESULTS

After adjusted for potential confounders, the rate of embryonic aneuploidy and embryonic mosaic in PCOS group were comparable with control group [embryonic aneuploid rate PCOS group: 14.0% vs control group: 18.3%, adjusted OR (95%CI): 0.78(0.54,1.12), P = 0.19; embryonic mosaic rate 10.9% vs 10.1%, adjusted OR (95%CI): 0.91(0.59,1.40), P = 0.66]. We further stratified PCOS women into four groups according to phenotype. The rate of aneuploid and mosaic embryos was comparable between each of PCOS phenotype and control group. There was still no significant difference of embryonic aneuploid and embryo mosaic rates within four phenotypes.

CONCLUSIONS

The risk of aneuploid and mosaic embryos was not increased in PCOS women. Thus, we suggests that the miscarriage rate arising from abnormal embryonic chromosomes could be similar between PCOS and non-PCOS women.

Association between embryo morphological quality and birth weight for singletons conceived via autologous fresh embryo transfer: an analysis using Society for Assisted Reproductive Technology Clinical Outcomes Reporting System

OBJECTIVE

To determine if morphologically suboptimal embryo quality is associated with adverse perinatal outcomes.

DESIGN

A retrospective cohort.

SETTING

SART CORS database.

PATIENT(S)

Singletons conceived from autologous in vitro fertilization fresh cycles.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Birth weight (gram), birth weight z-score, low birth weight (LBW), small for gestational age (SGA), and large for gestational age (LGA).

RESULT(S)

Among 5,869 in vitro fertilization fresh cycles, 71.1% transferred morphologically good embryos, and 27.0% and 1.9% transferred fair and poor embryo(s), respectively. Compared with singletons conceived from good embryos, singletons from poor embryos had a higher birth weight (3,415.8 ± 562.0 vs. 3,202.7 ± 639.9). Proportions of LBW, SGA, and LGA were comparable across embryo quality groups. Multivariate regression analysis comparing perinatal outcomes from fair vs. good embryos showed no association for birth weight (0.69-gram difference; 95% CI, -24.30-25.68), birth weight z-score (Coefficient, 0.00; 95% CI, -0.07-0.08), LBW (adjusted odds ratio [aOR], 0.84; 95% CI, 0.63-1.11), SGA (aOR, 0.93; 95% CI, 0.78-1.11), and LGA (aOR, 1.07; 95% CI, 0.86-1.33). Stratified analysis, considering cleaved and blastocyst embryo transfers separately, confirmed these findings. Sensitivity analysis revealed increased odds of LGA (aOR, 1.53; 95% CI, 1.04-2.24) with fair-quality embryos only among single embryo transfer cycles.

CONCLUSION(S)

Once a singleton live birth from fresh embryo transfer is achieved, fair morphological embryo quality is not associated with a reduction in birth weight or increased risks of LBW, SGA, and LGA.

The influence of morphologic grading and COS protocol on the outcomes of Day 5 versus Day 6 single fresh blastocyst transfers: a retrospective analysis of clinical outcomes from one center experience

INTRODUCTION

The purpose of this study was to evaluate whether the blastocyst morphologic grading and the protocol of controlled ovarian stimulation (COS) would influence pregnancy outcomes, aiming to provide guidance when choosing blastocyst transfer.

METHODS

The clinical data of 612 patients who received single fresh blastocyst transfer for first cycle, as well as the data of 253 patients who had already delivered were analyzed retrospectively. The patients were divided into two groups according to blastocyst formation time (D5 or D6). The following subgroup analyses were performed: (i) the morphologic grading of blastocyst and (ii) the protocol of COS.

RESULTS

We observed that D5 single embryo transfer (SET) were associated with higher clinical pregnancy rate (CPR, 59.04% vs. 31.73%, P < 0.001) and live birth rate (LBR, 43.90% vs. 24.04%, P < 0.001) than D6 SET following fresh cycle. Patients in D5 group experienced more good blastocysts transfer (45.47%vs. 13.46%, P < 0.001) and less poor blastocysts transfer (9.64%vs. 45.19%, P < 0.001) than patients in D6 group. As to early stage and good quality blastocysts, the CPR and LBR were similar between D5 and D6 group. GnRH antagonist protocol had a demonstrable inferiority comparing with the early-follicular-phase long-acting GnRH-agonist long protocol (EFLL) or the mid-luteal-phase long-acting GnRH-agonist long protocol (MLLL) with regard to the CPR and LBR in D6-SET group.

CONCLUSIONS

The analysis found that ovarian reserve of patients in D6-SET group was comparatively worse than that of patients in D5-SET group and D6-SET patients represented a subgroup of infertility patients usually having relatively poor embryo quality. The results should be interpreted with caution as the very low numbers in the respective group limited the use of statistical tests and the real significance values.

Incidence, dynamics and recurrences of reverse cleavage in aneuploid, mosaic and euploid blastocysts, and its relationship with embryo quality

Background

During embryonic development, the normality of cleavage and the ploidy state are closely related to the final clinical outcome. At present, many research teams are focusing on the combined application of timelapse (TL) technology and preimplantation genetic testing (PGT) technology, hoping to find a connection between the two aspects of morphodynamics and genes. In the process of embryonic cleavage, there is a common abnormal cleavage pattern called reverse cleavage (RC). RC refers to blastomere fusion and failed cytokinesis. There are very few reports about it. Whether the occurrence of RC affects blastocyst euploidy is even less clear. Whether the RC phenomenon affects the embryonic developmental potential and whether it is related to the embryo ploidy. This is important for clinicians and embryologists. In this study, we used TL to observe whether there was a phenomenon of RC in each biopsy embryo and then combined it with the ploidy state to give an answer, which provided support for the selection strategy of RC embryos.

Methods

A total of 405 TL-PGT cycles and 1,467 blastocysts were included in the study. All TL data were collected from the Reproductive Medicine Center, Huazhong University of Science and Technology Hospital. Embryos images throughout embryonic development, from post-insemination to day 5 or 6 until biopsy and cryopreservation, were acquired by the Embryoscope Plus TL microscopy system from January 2019 to December 2020. This study investigated the overall incidence of RC during cleavage; the relationship between RC phenomenon and the number of occurrences and ploidy results; the relationship between RC occurrence and blastocyst developmental quality, as well as the dynamics of RC embryos.

Results

Among the 1,453 blastocysts biopsied, 400 blastocysts showed RC phenomenon at the cleavage stage, and the incidence rate was 25.9%. In euploid, mosaic and aneuploid embryos, the incidence of RC was 27.2%, 26.6%, and 25.0%, respectively. The incidence of RC was similar among these three groups with no significant difference (P > 0.05). The number of RC occurrences was not associated with embryo ploidy status (P > 0.05). In general, the blastocyst quality of the RC + group was lower than that of the RC- group. In the ICM score, the proportion of A score in the RC + group was significantly lower than that in RC- group (P < 0.05). In the TE score, there was no significant difference between the two groups of A-grade blastocysts, but the proportion of B-grade blastocysts in the RC + group was significantly lower than that in the RC- group (P < 0.01). In terms of developmental kinetic parameters, the cleavage synchrony parameters s2 and s3 were significantly longer in RC + embryos than in RC- embryos (P < 0.05). However, these changes in kinetic parameters were not significantly different between the euploid, mosaic and aneuploid groups.

Conclusions

The chromosomal euploidy of cleavage-stage embryos with RC phenomenon developed to the blastocyst stage was not significantly different from that of cleavage normal blastocysts. Therefore, RC embryos should not be discarded. It is recommended to select and utilize blastocyst culture, which has similar clinical value to normal cleavage embryos.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-01026-9.

Live birth rate following a euploid blastocyst transfer is not affected by double vitrification and warming at cleavage or blastocyst stage

PURPOSE

To compare reproductive outcomes following a euploid embryo transfer, between those embryos vitrified-warmed twice to those vitrified-warmed once.

METHODS

We retrospectively analysed 694 single euploid frozen embryo transfer cycles following preimplantation genetic testing for aneuploidy (PGT-A). For cycles in group 1 (N = 451), embryos were biopsied for PGT-A at blastocyst stage and vitrified. For cycles in group 2 (N = 146), embryos were vitrified at blastocyst stage, before being warmed and biopsied for PGT-A and vitrified again. For cycles in group 3 (N = 97), embryos were vitrified on day-3, before being warmed, cultured to day-5 and biopsied for PGT-A and re-vitrified.

RESULTS

The pregnancy, clinical pregnancy and livebirth rate in group 2 were not statistically different to group 1 (pregnancy rate, adjusted OR 1.09, 95% CI 0.62-1.91; clinical pregnancy, aOR 0.89, 95% CI 0.58-1.37; live birth rate, aOR 0.85, 95% CI 0.56-1.28). There was also no significant difference between group 3 and group 1, with similar pregnancy rate (aOR 1.22, 95% CI 0.74-1.99), clinical pregnancy rate (aOR 1.21, 95% CI 0.75-1.96) and live birth rate (aOR 1.15, 95% CI, 0.73-1.80). There was no significant difference in miscarriage rates between all three groups. The age at the oocyte collection, embryo quality and day of biopsy were associated with pregnancy, clinical pregnancy and live birth rate.

CONCLUSION

This study suggests that vitrifying and warming embryos twice at blastocyst or at cleavage and then blastocyst stage, can lead to similar reproductive outcomes to embryos vitrified-warmed once, after a single euploid embryo transfer.

Perinatal outcomes of singleton live births after preimplantation genetic testing during single frozen-thawed blastocyst transfer cycles: a propensity score-matched study

OBJECTIVE

To determine whether singleton pregnancy achieved after preimplantation genetic testing (PGT) is associated with a higher risk of adverse perinatal outcomes than in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) singleton pregnancy.

DESIGN

A retrospective cohort study.

SETTING

A university-affiliated fertility center.

PATIENT(S)

This cohort study included singleton live births resulting from PGT (n = 232) and IVF/ICSI singleton pregnancies (n = 2,829) with single frozen-thawed blastocyst transfer. Multiple baseline covariates were used for propensity score matching, yielding 214 PGT singleton pregnancies matched to 617 IVF/ICSI singleton pregnancies.

INTERVENTION(S)

Trophectoderm biopsy.

MAIN OUTCOME MEASURE(S)

The primary outcome was gestational hypertension, and various clinical perinatal secondary outcomes related to maternal and neonatal health were measured.

RESULT(S)

Compared with IVF/ICSI singleton pregnancy, PGT singleton pregnancy was associated with a significantly higher risk of gestational hypertension (adjusted odds ratio, 2.58; 95% confidence interval, 1.32, 5.05). In the matched sample, the risk of gestational hypertension remained higher with PGT singleton pregnancy (odds ratio, 2.33; 95% confidence interval, 1.04, 5.22) than with IVF/ICSI singleton pregnancy. No statistical differences were noted in any other measured outcomes between the groups.

CONCLUSION(S)

The perinatal outcomes of PGT and IVF/ICSI singleton pregnancies were similar except for the observed potentially higher risk of gestational hypertension with PGT singleton pregnancy. However, because the data on PGT singleton pregnancies are limited, this conclusion warrants further investigation.

Day 5 vs day 6 single euploid blastocyst frozen embryo transfers: which variables do have an impact on the clinical pregnancy rates?

OBJECTIVE

To determine which variables affect most the clinical pregnancy rate with positive fetal heartbeat (CPR FHB+) when frozen embryo transfer (FET) cycles are performed with day 5 (D5) or day 6 (D6) euploid blastocysts. Design and method A single center retrospective study was performed from March 2017 till February 2021 including all single FET cycles with euploid D5 or D6 blastocysts and transferred in natural cycles (NC) or hormone replacement therapy (HRT) cycles. Trophectoderm (TE) and inner cell mass (ICM) qualities were recorded before biopsy.

RESULTS

A total of 1102 FET cycles were included, 678 with D5 and 424 with D6 blastocysts. Pregnancy rate (PR), clinical PR (CPR), and CPR FHB+ were significantly higher with D5 blastocysts (PR: 70.7% vs 62.0%, OR = 0.68 [0.53-0.89], p = 0.004; CPR: 63.7% vs 54.2%, OR = 0.68 [0.52-0.96], p = 0.002 and CPR FHB+: 57.8% vs 49.8%, OR = 0.72 [0.53-0.96], p = 0.011). However, miscarriage rate (12.5% vs 11.4%, OR = 0.78 [0.48-1.26], p = 0.311) did not differ. From a multivariate logistic regression model, endometrial thickness (OR = 1.11 [1.01-1.22], p = 0.028), patient's age (OR = 1.03 [1.00-1.05], p = 0.021), BMI (OR = 0.97 [0.94-0.99], p = 0.023), and ICM grade C (OR = 0.23 [0.13-0.43], p < 0.001) were significant in predicting CPR FHB+.

CONCLUSION

Although clinical outcomes are higher with D5 blastocysts, CPR FHB+ is more affected by endometrial thickness, patient age, BMI, and ICM grade C rather than biopsy day or endometrial preparation protocol.

Blastocyst quality and perinatal outcomes of frozen-thawed single blastocyst transfer cycles

OBJECTIVE

To investigate the effects of blastocyst quality and morphological grade on the perinatal outcomes in patients undergoing frozen-thawed single blastocyst transfer cycles.

METHODS

This single-center retrospective cohort study included 2648 singleton neonates resulting from frozen-thawed single blastocyst transfers performed between January 2017 and September 2021. Multivariate logistic regression was performed to evaluate perinatal outcomes for their association with blastocyst quality and morphological parameters.

RESULT

Transfer of a good-quality blastocyst in a frozen-thawed cycle was associated with a lower rate of preterm delivery (PTD, adjusted OR =0.7, 95% CI 0.5-0.9; P=0.020) and a higher likelihood of a male neonate (adjusted OR =1.2, 95%CI 1.0-1.5; P=0.048). Compared with grade C inner cell mass (ICM) blastocyst transfer, grade B ICM (adjusted OR =0.5, 95%CI 0.2-0.9; P=0.027) and grade A ICM (adjusted OR =0.6, 95%CI 0.3-1.5; P=0.290) blastocyst transfers were associated with a lower rate of PTD, which was more evident for grade B ICM. After adjusting for confounders, the likelihood of a male neonate (grade B TE, OR =1.2, 95%CI 1.0-1.5, P=0.037; grade A TE OR =1.9, 95%CI 1.3-28, P=0.002) increased with increasing trophectoderm (TE) quality. Compared with expansion stage 4, the likelihood of a male neonate was 1.5 times greater with transfer of a stage 6 blastocyst (OR =1.5, 95%CI 1.0-2.3; P=0.06), and the risk of small for gestational age (SGA) was greater with transfer of a stage 5 blastocyst (adjusted OR =3.5, 95%CI 1.5-8.0; P=0.004). The overall grading of the blastocyst, expansion stage, ICM grade, and TE grade were not associated with length at birth, birthweight, large for gestational age (LGA), or birth defects (all P>0.05).

CONCLUSIONS

In frozen-thawed single blastocyst transfer cycles, transfer of a good-quality blastocyst was associated with a lower rate of PTD and a greater likelihood of a male neonate. Transfer of grade B ICM blastocysts decreased the rate of PTD, and TE quality was positively correlated with the likelihood of a male neonate.

Effect of Blastocyst Morphology and Developmental Rate on Euploidy and Live Birth Rates in Preimplantation Genetic Testing for Aneuploidy Cycles With Single-Embryo Transfer

OBJECTIVE

The aim of this study was to investigate whether blastocyst morphology and developmental rate are associated with euploidy and live birth rates (LBRs) in single euploid frozen-thawed embryo transfer (FET) cycles.

DESIGN

Retrospective cohort study.

METHODS

This study included 431 preimplantation genetic testing for aneuploidy (PGT-A) cycles followed by 393 FET cycles performed at our center from June 2017 to March 2021. All cycles were analyzed for euploidy based on blastocyst morphology (good, average and poor), developmental stage (day 5 and 6) and maternal age (< 35 and ≥ 35 years old). Multivariate logistic analysis models were used to identify the independent effects of conventional blastocyst morphology, developmental rate and morphological parameters (degree of blastocoele expansion, and grade of inner cell mass and trophectoderm (TE)) on LBRs.

RESULTS

In the group of women aged < 35 years, compared with poor-quality blastocysts, good-quality blastocysts (62.90% vs. 32.46%; odds ratio (OR) 3.163, 95% confidence interval (CI) 2.247-4.451; P < 0.001) and average-quality blastocysts (46.70% vs. 32.46%; OR 1.665, 95% CI 1.287-2.154; P < 0.001) had significantly higher euploidy rates. Additionally, day 5 blastocysts were associated with higher euploidy rates than day 6 blastocysts (49.28% vs. 35.02%; OR 1.506, 95% CI 1.191-1.903; P= 0.001). In the group of women aged ≥ 35 years, euploidy rates were also associated with blastocyst morphology, with 41.86%, 45.65% and 24.39% of good, average and poor-quality embryos, respectively, exhibiting euploidy. However, no relationship was seen between euploidy and blastocyst developmental rate. Multiple logistic regression analysis show that overall blastocyst morphology of euploid embryos was not associated with LBR, only embryos with A-grade TE had significantly higher LBRs than those with C-grade TE (62.71% vs. 45.40%; OR 2.189, 95% CI 1.166-4.109; P=0.015). Similarly, LBRs were significantly higher when day 5 blastocysts were transferred than when day 6 blastocysts were transferred (57.75% vs. 41.67%; OR 2.132, 95% CI 1.370-3.318; P = 0.001).

CONCLUSION

Poor-quality embryos have reduced rates of euploidy. However, blastocyst developmental rate only significantly associates with euploidy rates in women aged younger than 35. Furthermore, only TE grade and blastocyst developmental rate are significantly associated with LBRs following FET cycles.

Association between clinical and IVF laboratory parameters and miscarriage after single euploid embryo transfers

BACKGROUND

The goal of this study was to investigate which factors, excluding embryo aneuploidies, are associated with miscarriage in patients who have undergone a single euploid blastocyst transfer.

METHODS

Retrospective, observational and multicenter study with 2832 patients undergoing preimplantational genetic testing for aneuploidies (PGT-A) due to repeated implantation failure, recurrent pregnancy loss, advanced maternal age or severe male factor were transferred one single euploid embryo.

RESULTS

One of the main findings was a significant relationship between body mass index (BMI) and miscarriage rates (13.4% in underweight women, 12.1% in normal weight, 14.5% in overweight, and 19.2% in obese women, odds ratio [OD] 1.04; 95% confidence interval [CI], 1.01-1.07 p = 0.006). Endometrial thickness (OD 0.65; 95%, 0.52-0.77 p = 0.04) and type of endometrial preparation (natural cycle or hormone replacement cycle) (OD 0.77; 95%, 0.52-0.77, p = 0.04) were also associated with miscarriage rates.

CONCLUSIONS

BMI was strongly associated to miscarriage rates. We also observed a weaker association with endometrial thickness and with the type of endometrial preparation (natural cycle or hormone replacement cycle). None of the other studied variables (biopsy day, maternal and male age, duration of infertility, cycle length, previous miscarriages, previous live births, previous In Vitro Fertilization (IVF) cycles, endometrial pattern and/or diagnosis) were associated with miscarriage rates.

Efficiency and safety of laser-assisted hatching on vitrified-warmed blastocyst transfer cycles: a prospective control trial

To clarify the efficiency and safety of laser-assisted hatching (LAH) application on vitrified-warmed blastocyst transfer (VBT) cycles, we designed the non-randomized concurrent control trial included 4039 VBT cycles in the Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, during the even days from November 2014 to December 2015. The VBT cycles were divided into LAH group (n = 1932) and non-LAH group (n = 2107) according to the date of blastocyst thawing. Laser-partial zona pellucida dissection was performed on all blastocysts thawed on that day every 4 days, and those blastocysts were assigned to the LAH group. There were a higher biochemical pregnancy rate (66.87% vs 63.69%; P = 0.034; rate ratio for LAH vs non-LAH group [RR], 1.050; 95% confidence interval [CI], 1.004-1.098) and an increased live birth rate (48.81% vs 45.51%; P = 0.036; RR, 1.072; 95% CI, 1.005-1.145) with comparable ectopic pregnancy, twin or multiple pregnancies, spontaneous abortion and birth defect rates of the LAH group than those of the non-LAH group. Subgroup analysis showed that live birth rate, birth defect rate, and other pregnancy outcomes were comparable for patients younger than 35 years when blastocyst transfer, patients with endometrium thickness less than 0.9 cm during ovulation or the initiation of progesterone treatment, ICSI blastocysts, AC or BC blastocysts according to Gardner morphological criteria and day 5 blastocysts of the LAH group than it of non-LAH group. LAH could be performed selectively on vitrified-warmed blastocysts before transfer for better pregnancy outcomes. Trial registration number: ChiCTR2000032975. Date of registration: May 17, 2020. Retrospectively registered.

Perinatal Outcomes of Singleton Live Births Following Preimplantation Genetic Testing for Chromosomal Structural Rearrangements in Single Frozen-Thawed Blastocyst Transfer Cycles: a Retrospective Cohort Study

This study investigated whether singleton pregnancies conceived after preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) are associated with a higher risk of adverse perinatal outcomes than singleton pregnancies conceived after intracytoplasmic sperm injection (ICSI). We collected data on singleton live births after PGT-SR (n = 107) and ICSI (n = 585) in our hospital from January 2017 to August 2020. Multivariable analyses were used to adjust for maternal age, body mass index, gravidity and parity, paternal age, ovulatory disorder, and recurrent spontaneous abortion. The unadjusted results showed a significantly higher risk of hypertensive disorders of pregnancy (HDP) (odds ratio (OR) = 2.47; 95% confidence interval (CI): 1.10-5.54; P = 0.029) associated with PGT-SR singleton pregnancies than with ICSI singleton pregnancies. However, after adjusting for potential confounders, there were no longer any significant differences in the risk of HDP (adjusted OR = 2.24; 95% CI: 0.92-5.48; P = 0.077) between PGT-SR and ICSI singleton pregnancies. There were no significant differences between PGT-SR and ICSI singleton pregnancies in terms of gestational diabetes, preterm premature rupture of membranes, placenta previa, cesarean delivery, gestational age (weeks), preterm delivery (< 37 weeks), very preterm delivery (≥ 28 weeks and < 32 weeks), birth weight (g), low birth weight (< 2500 g), very low birth weight (< 1500 g), birth height (cm), birth defects, and 1-min and 5-min Apgar scores. In conclusion, for single frozen-thawed blastocyst cycles, there were no significant differences in adverse perinatal outcomes between PGT-SR and ICSI singleton pregnancies. However, due to the limited sample size, these conclusions need to be confirmed by further studies.

Effect of blastocyst morphology and developmental speed on transfer strategy for grade "C" blastocyst in vitrified-warmed cycles

BACKGROUND

High-quality single blastocyst transfer (SBT) is increasingly recommended to patients because of its acceptable pregnancy outcomes and significantly reduced multiple pregnancy rate compared to double blastocyst transfer (DBT). However, there is no consensus on whether this transfer strategy is also suitable for poor-quality blastocysts. Moreover, the effect of the development speed of poor-quality blastocysts on pregnancy outcomes has been controversial. Therefore, this study aimed to explore the effects of blastocyst development speed and morphology on pregnancy and neonatal outcomes during the frozen embryo transfer (FET) cycle of poor-quality blastocysts and to ultimately provide references for clinical transfer strategies.

METHODS

A total of 2,038 FET cycles of poor-quality blastocysts from patients 40 years old or less were included from January 2014 to December 2019 and divided based on the blastocyst development speed and number of embryos transferred: the D5-SBT (n = 476), D5-DBT (n = 365), D6-SBT (n = 730), and D6-DBT (n = 467) groups. The SBT group was further divided based on embryo morphology: D5-AC/BC (n = 407), D5-CA/CB (n = 69), D6-AC/BC (n = 580), and D6-CA /CB (n = 150).

RESULTS

When blastocysts reach the same development speed, the live birth and multiple pregnancy rates of DBT were significantly higher than those of SBT. Moreover, there was no statistical difference in the rates of early miscarriage and live birth between the AC/BC and CA/CB groups. When patients in the SBT group were stratified by blastocyst development speed, the rates of clinical pregnancy (42.44 % vs. 20.82 %) and live birth (32.35 % vs. 14.25 %) of D5-SBT group were significantly higher than those of D6-SBT group. Furthermore, for blastocysts in the same morphology group (AC/BC or CA/CA group), the rates of clinical pregnancy and live birth in the D5 group were also significantly higher than those of D6 group.

CONCLUSIONS

For poor-quality D5 blastocysts, SBT can be recommended to patients because of acceptable pregnancy outcomes and significantly reduced multiple pregnancy rate compared with DBT. For poor-quality D6, the DBT strategy is recommended to patients to improve pregnancy outcomes. When blastocysts reach the same development speed, the transfer strategy of selecting blastocyst with inner cell mass "C" or blastocyst with trophectoderm "C" does not affect the pregnancy and neonatal outcomes.

Mitochondrial DNA Content May Not Be a Reliable Screening Biomarker for Live Birth After Single Euploid Blastocyst Transfer

An increasing number of studies have related the mitochondrial DNA (mtDNA) content to embryo viability and transfer outcomes. However, previous studies have focused more on the relationship between mtDNA and embryo implantation, few studies have studied the effect of the mtDNA content on live birth. In the study, we investigated whether mtDNA content is a reliable screening biomarker for live birth after single blastocyst transfer. A total of 233 couples with 316 blastocyst stage embryos undergoing in vitro fertilization treatment and pre-implantation genetic testing analysis were included in the study. All embryos were chromosomally normal and had undergone single-embryo transfers. There was no significant difference observed in the blastocyst mtDNA content among the live birth, miscarriage and non-implanted groups (p=0.999), and the mtDNA content in blastocysts from the miscarriage and live birth groups was similar [median (interquartile range), 1.00*10⁸(7.59*10⁷- 1.39*10⁸) vs 1.01*10⁸ (7.37*10⁷- 1.32*10⁸)]. Similarly, no significant association was observed between mtDNA content and embryo implantation potential (p=0.965). After adjusting for multiple confounders in a logistic regression analysis with generalized estimating equations, no associations between mtDNA content and live birth were observed in all blastocysts, Day-5 and Day-6 blastocysts (p=0.567, p=0.673, p=0.165, respectively). The live birth rate was not significantly different between blastocysts with an elevated mtDNA content and blastocysts with a normal mtDNA content (26.7% vs 33.6% p=0.780). Additionally, there was no linear correlation between the mtDNA content and maternal age (p=0.570). In conclusion, the mtDNA content does not seem to be a potential biomarker for embryo transfer outcomes (i.e., implantation and live birth) based on the existing testing tools. Embryos with an elevated mtDNA content also have development potential for successful live birth.

History of Recurrent Implantation Failure is Associated With the Incidence of Adverse Perinatal Outcomes in Singleton Live Births Following Frozen-Thawed Embryo Transfer Cycles

OBJECTIVE

To investigate whether patients with a history of recurrent implantation failure (RIF) are associated with adverse perinatal outcomes in singleton live births following frozen-thawed embryo transfer (FET) cycles.

DESIGN

Retrospective cohort study.

METHODS

This study analyzed the obstetric and neonatal outcomes of patients with and without a history of RIF who underwent FET cycles in a single reproductive center between January 2017 and October 2020. A total of 1,100 women with singleton live births beyond 28 weeks of gestation were included. The primary outcome measures were perinatal outcomes, especially gestational age, birthweight, preterm birth (PTB), large for gestational age (LGA), small for gestational age (SGA), congenital malformation rates, and premature rupture of the membranes (PROM). Multiple logistic regression was used to establish relationships between RIF and adverse perinatal outcomes after adjusting for relevant baseline demographics and cycle characteristics.

RESULTS

The RIF group showed a preferred transfer of two embryos and cleavage embryos compared with the control group (P <0.05). Regarding perinatal outcomes in singleton deliveries, women with RIF had increased rates of LBW (adjusted odds ratio [aOR] 2.027; 95% confidence interval [CI], 1.025-4.009), PTB (aOR 1.785; 95% CI, 1.050-3.036), and PROM (aOR 2.259; 95% CI, 1.142-4.467). The incidence of congenital malformations was similar between the two groups (4.1% vs. 2.4%; P = 0.759). Furthermore, multiple intrauterine procedures were associated with a statistically significant increased risk of PROM in RIF patients (aOR 1.537; 95% CI, 1.105-2.137).

CONCLUSIONS

Women with a history of RIF were associated with an increased risk of LBW, PTB, and PROM in singleton live births after FET cycles. In addition, multiple intrauterine procedures were independent risk factors for PROM.