Comparison of the clinical outcomes of day 4 and 5 embryo transfer cycles

Which transfer day results in the highest live birth rate for PCOS patients undergoing in vitro fertilization?

BACKGROUND

Polycystic ovary syndrome (PCOS) has unusual levels of hormones. The hormone receptors in the endometrium have a hostile effect and make the microenvironment unfavorable for embryo implantation. The use of gonadotropin stimulation during in vitro fertilization (IVF) may have an impact on embryo implantation and live birth rate. According to recent data, the clinical results of day 4 embryo transfer (D4 transfer) were on par with those of day 5 embryo transfer (D5 transfer) in IVF-ET. There are few studies comparing the outcomes of transplants with various etiologies and days. The purpose of this study was to determine which transfer day had the best result for PCOS patients undergoing IVF.

METHODS

This retrospective cohort study was conducted in the Xingtai Infertility Specialist Hospital between January 2017 and November 2021. A total of 1,664 fresh ART cycles met inclusion criteria, including 242 PCOS transfers and 1422 tubal factor infertility transfers.

CONCLUSIONS

PCOS individuals had the highest live birth rate on D4 transferred. It was not need to culture embryos to blastocysts to optimize embryo transfer for PCOS women. This could be a novel approach to transplantation for PCOS.

Conceptus interferon gamma is essential for establishment of pregnancy in the pig

Establishment and maintenance of pregnancy in the pig is a complex process that relies on conceptus regulation of the maternal proinflammatory response to endometrial attachment. Following elongation, pig conceptuses secrete interferon gamma (IFNG) during attachment to the endometrial luminal epithelium. The objective here was to determine if conceptus production of IFNG is important for early development and establishment of pregnancy. CRISPR/Cas9 gene editing and somatic cell nuclear transfer technologies were used to create an IFNG loss-of-function study in pigs. Wild-type (IFNG+/+) and null (IFNG-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer. IFNG expression was not detected in IFNG-/- conceptuses on either day 15 or day 17 of pregnancy. Ablation of conceptus IFNG production resulted in the reduction of stromal CD3+ and mast cells which localized to the site of conceptus attachment on day 15. The uteri of recipients with IFNG-/- conceptuses were inflamed, hyperemic and there was an abundance of erythrocytes in the uterine lumen associated with the degenerating conceptuses. The endometrial stromal extracellular matrix was altered in the IFNG-/- embryo pregnancies and there was an increased endometrial mRNA levels for collagen XVII (COL17A1), matrilin 1 (MATN1), secreted phosphoprotein 1 (SPP1) and cysteine-rich secretory protein 3 (CRISP3), which are involved with repair and remodeling of the extracellular matrix. These results indicate conceptus IFNG production is essential in modulating the endometrial proinflammatory response for conceptus attachment and survival in pigs.

Ablation of conceptus PTGS2 expression does not alter early conceptus development and establishment of pregnancy in the pig†

Pig conceptuses secrete estrogens (E2), interleukin 1 beta 2 (IL1B2), and prostaglandins (PGs) during the period of rapid trophoblast elongation and establishment of pregnancy. Previous studies established that IL1B2 is essential for rapid conceptus elongation, whereas E2 is not essential for conceptus elongation or early maintenance of the corpora lutea. The objective of the present study was to determine if conceptus expression of prostaglandin-endoperoxide synthase 2 (PTGS2) and release of PG are important for early development and establishment of pregnancy. To understand the role of PTGS2 in conceptus elongation and pregnancy establishment, a loss-of-function study was conducted by editing PTGS2 using CRISPR/Cas9 technology. Wild-type (PTGS2+/+) and null (PTGS2-/-) fibroblast cells were used to create embryos through somatic cell nuclear transfer. Immunolocalization of PTGS2 and PG production was absent in cultured PTGS2-/- blastocysts on day 7. PTGS2+/+ and PTGS2-/- blastocysts were transferred into surrogate gilts, and the reproductive tracts were collected on either days 14, 17, or 35 of pregnancy. After flushing the uterus on days 14 and 17, filamentous conceptuses were cultured for 3 h to determine PG production. Conceptus release of total PG, prostaglandin F2⍺ (PGF2α), and PGE in culture media was lower with PTGS2-/- conceptuses compared to PTGS2+/+ conceptuses. However, the total PG, PGF2α, and PGE content in the uterine flushings was not different. PTGS2-/- conceptus surrogates allowed to continue pregnancy were maintained beyond 30 days of gestation. These results indicate that pig conceptus PTGS2 is not essential for early development and establishment of pregnancy in the pig.

Comparison of Pregnancy Outcomes Between Single-Morula Embryo Transfer and Single-Blastocyst Transfer in Fresh IVF/ICSI Cycles

BACKGROUND This study investigated the effectiveness and feasibility of day 4 (D4) morula embryo transfer (ET) in comparison with day 5 (D5) blastocyst ET, with regards to their clinical data, laboratory test results, and pregnancy outcomes. MATERIAL AND METHODS This retrospective cohort study enrolled 1070 patients, including 178 cases in group D4 and 892 cases in group D5. The endpoint was live birth rate after fresh embryo transfer. Furthermore, the clinical outcomes of D4 embryos with different morphology were compared and assigned to 3 groups: in group 1 (n=66) the embryos were compacted but not expanded, in group 2 (n=102) the embryos were compacted and expanded (early blastocyst), and in group 3 (n=10) the embryos were not compacted. RESULTS Groups D4 and D5 had comparable clinical pregnancy rates (53.37% vs. 59.97%) and live birth rates (43.25% vs 50.89%), and there were no significant differences between the 2 groups. In group 3, there was only 1 clinical pregnancy and no live birth. In comparison between group 1 and group 2, the clinical pregnancy rate of group 2 showed an upward trend (48.48% vs 60.78%), but there was no significant difference. There was also no statistically significant difference in the live birth rate between the 2 groups (42.42% vs 49.01%). CONCLUSIONS Transferring of compacted embryos or early blastocysts can result in high clinical pregnancy rates and live birth rates. In addition to the cleavage and blastocyst ET, morula ET may serve as an alternative option for the clinician.

A New Day 4 Grading System to Assess Embryo Quality in Frozen Embryo Transfer Cycles

To present a new day 4 (D4) embryo grading system to assess embryos in frozen-thawed embryo transfer (FET) cycles. A new grading system (grades A-E) was developed from the 2011 ESHRE Istanbul Consensus for D4 embryos in FET cycles. Embryos with complete compaction were classified as grade A; those with partial compaction were assigned as grade B; and those without compaction were classified as grades C, D, and E according to their different blastomere number ratio (BNR; number of embryo blastomeres on D4/number of embryo blastomeres on D3, D4/D3). Embryos with a BNR of ≥ 1.5 were defined as grade C, those with a BNR of ≥ 1.2 and < 1.5 were defined as grade D, and those with a BNR of ≥ 1.0 and < 1.2 were defined as grade E. Using this proposed grading model, 5460 embryos with known implantation data were retrospectively analyzed after D4 transfer in FET cycles. The transferred embryos exhibited a similar declining trend in implantation and live birth rates from the top grade A to the lowest grade E. The in vitro fertilization group showed increased implantation rates of grade B and E embryos compared with the intracytoplasmic sperm injection group (grade B: 41.99%, 34.63%, χ² = 5.84, p < 0.05 and grade E: 18.98%, 14.08, χ² = 75.62, p < 0.01). Receiver-operating characteristic analysis revealed that our proposed model predicted the implantation outcomes and live birth rates of all embryos (area under the curve = 0.65; 95% confidence interval [CI],0.63-0.66; p < 0.01 and AUC = 0.73; 95%CI, 0.65-0.84; p < 0.001, respectively). This study demonstrates that the new grading system provided by us can be a useful tool for assisting embryo selection via changes in embryo morphology. D4 embryo transfer provides a simple and applicable method for FET cycles in daily practice.

Associations between a new day 4 embryo grading system and implantation rates in frozen embryo transfer (FET) cycles

The purpose of this study is to present a new day 4 (D4) embryo grading system for the assessment of embryos in frozen-thawed embryo transfer (FET) cycles.A new grading system (grades A-E) was modified from the 2011 ESHRE Istanbul Consensus for D4 embryos in FET cycles. In total, we retrospectively analyzed 5640 embryos with known implantation data after D4 transfer in FET cycles by using this proposed grading model.The transferred embryos exhibited a similar declining trend in implantation rates from the top grade A to the lowest grade E. The implantation rates of grade B and E embryos in the in vitro fertilization group were significantly higher than that in the intracytoplasmic sperm injection group (grade B: 41.82%, 35.23%, χ = 5.85, P < .05 and grade E: 18.53%, 14.81, χ = 76.86, P < .01, respectively). The receiver operating characteristic analysis showed that our proposed model predicted the implantation outcomes of all embryos (area under the ROC curve = 0.65; 95% CI, 0.63-0.66; P < .01).This study demonstrated that the new grading system provided by us turned out to be a useful tool in assisting embryo selection via embryo morphological changes, and D4 embryo transfer provided a simple and applicable method for a daily routine in FET cycles.

Should the flexibility enabled by performing a day-4 embryo transfer remain as a valid option in the IVF laboratory? A systematic review and network meta-analysis

PURPOSE

The present systematic review and network meta-analysis aims to uniquely bring to literature data supporting the true place of the alternative practice of day-4 embryo transfer (D4 ET) in an IVF laboratory, beyond the one-dimensional option of facilitating a highly demanding program.

METHODS

A systematic search was conducted in the databases of PubMed/Medline, Embase, and Cochrane Central Library, resulting to six prospective along with nine retrospective cohort studies meeting eligibility criteria for inclusion. A comparison of D4 ET with day-2 (D2), day-3 (D3), and day-5 (D5) ET, respectively, was performed employing R statistics.

RESULTS

The sourced results indicate no statistically significant difference regarding clinical pregnancy rates, and ongoing pregnancy/live birth rates stemming from the comparison of D4 with D2, D4 with D3, and D4 with D5 ET, respectively. Additionally, no statistically significant difference could be established in respect to cancelation, and miscarriage rates, following the comparison of D4 with D3 and D4 with D5 ET. Interestingly, we report statistically significant lower preterm birth rates associated with D4 ET, in contrast with D5 ET (RR, 0.19; 95% CI, 0.05-0.67; p value = 0.01).

CONCLUSIONS

The aforementioned results may serve as advocates buttressing the option of D4 ET as a valid candidate in the ET decision-making process. Possible limitations of the current study are the publication bias stemming from the retrospective nature of certain included studies, along with various deviations among studies' design, referring to number and quality of transferred embryos, or different culture conditions referring to studies of previous decades.

Pregnancy rates of day 4 and day 5 embryos after culture in an integrated time-lapse incubator

BACKGROUND

The aim of this study was to compare pregnancy rates in patients undergoing IVF/ICSI with embryo transfer after 4 and 5 days of culture in a closed incubation system with integrated time-lapse imaging.

METHODS

Out of n = 2207 in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) cycles performed between January 2011 and April 2016 at a tertiary referral university hospital, a total of n = 599 IVF/ICSI cycles with prolonged embryo culture in an integrated time-lapse system (EmbryoScope^© (Vitrolife)) until day 4 or 5 were retrospectively analyzed with regard to embryo morphology and pregnancy rates.

RESULTS

A transfer on day 5 compared to a transfer on day 4 did not result in higher implantation and clinical pregnancy rates (IR 29.4% on day 4 versus 33.0% on day 5, p = 0.310; CPR 45.2% on day 4 versus 45.7% on day 5, p = 1.0). The percentage of ideal embryos transferred on day 4 was comparable to the rate of ideal embryos transferred on day 5 (41.6% versus 44.1%, p = 0.508). However, on day 4 a significantly higher number of embryos was transferred (1.92 on day 4 versus 1.84 on day 5, p = 0.023), which did not result in higher rates of multiple pregnancies.

CONCLUSIONS

Pregnancy rates in IVF/ICSI cycles with integrated time-lapse incubation and transfer on day 4 and 5 are comparable. This finding provides the clinician, IVF laboratory and patient with more flexibility.

TRIAL REGISTRATION

This study was retrospectively registered by the local ethics committee of the University of Heidelberg on December 19, 2016 (registration number S-649/2016).

Effects of maternal age on embryo quality and pregnancy outcomes using testicular sperm with intracytoplasmic sperm injection

Objective

The aim of this study was to evaluate the influence of maternal age on fertilization, embryo quality, and clinical pregnancy in patients undergoing intracytoplasmic sperm injection (ICSI) using testicular sperm from partners with azoospermia.

Methods

A total of 416 ICSI cycles using testicular spermatozoa from partners with obstructive azoospermia (OA, n=301) and non-obstructive azoospermia (NOA, n=115) were analyzed. Female patients were divided into the following age groups: 27 to 31 years, 32 to 36 years, and 37 to 41 years. The rates of fertilization, high-quality embryos, clinical pregnancy, and delivery were compared across maternal age groups between the OA and NOA groups.

Results

The rates of fertilization and high-quality embryos were not significantly different among the maternal age groups. Similarly, the clinical pregnancy and delivery rates were not significantly different. The fertilization rate was significantly higher in the OA group than in the NOA group (p<0.05). Age-group analysis revealed that the fertilization and high-quality embryo rates were significantly different between the OA and NOA groups in patients aged 27 to 31 years old, but not for the other age groups. Although the clinical pregnancy and delivery rates differed between the OA and NOA groups across all age groups, significant differences were not observed.

Conclusion

In couples using testicular sperm from male partners with azoospermia, pregnancy and delivery outcomes were not affected by maternal age. However, women older than 37 years using testicular sperm from partners with azoospermia should be advised of the increased incidence of pregnancy failure.

Efficacy of cryopreservation of embryos generated by intracytoplasmic sperm injection with spermatozoa from frozen testicular tissue

PURPOSE

To evaluate the viability of frozen embryos generated by intracytoplasmic sperm injection (ICSI) with frozen testicular spermatozoa.

METHODS

A total of 68 fresh embryo transfer (ET) cycles and 85 subsequent frozen-thawed ET (FET) cycles were grouped according to the source of spermatozoa: fresh testicular spermatozoa (TESE) or frozen-thawed testicular spermatozoa (t-TESE).

RESULTS

There were no significant differences in the age of female patients, number of oocytes, or fertilization rates in fresh ET cycles with TESE (TESE-fresh ET) versus t-TESE (t-TESE-fresh ET). The rate of embryo survival after thawing (95.7 % vs. 94.0 %) was similar in frozen ET cycles (FET) with TESE (TESE-FET) and with t-TESE (t-TESE-FET). While there were significant differences in the proportion of good quality embryos, no statistical differences were found in the pregnancy or clinical abortion rates between the two groups. Moreover, delivery rates were not significantly different.

CONCLUSIONS

Although the proportion of good quality embryos was affected by cryopreservation of testicular tissue, embryo survival rate was not. As well, subsequent pregnancy could be achieved successfully via t-TESE-FET cycles. Therefore, FET is not affected by the cryopreservation of testicular tissue, and avoids further oocyte retrieval and TESE procedures.