Improved detection of mineral oil toxicity using an extended mouse embryo assay

Purpose

Successful in vitro fertilization (IVF) relies on sound laboratory methods and culture conditions which depend on sensitive quality control (QC) testing. This study aimed to improve the sensitivity of mouse embryo assays (MEA) for detection of mineral oil toxicity.

Methods

Five experiments were conducted to study modifications of the standard mouse embryo assay (MEA) in order to improve sensitivity using clinical grade mineral oil with known peroxide concentrations. Assessment of blastocyst development at either 96 h or in an extended MEA (eMEA) to 144 h was tested in each experiment. In experiment 1, ability to detect peroxides in oil was compared in the MEA, eMEA, and cell number at 96 h. In experiment 2, serial dilutions of peroxide in oil were used along with time-lapse imaging to compare sensitivity of the morphokinetic MEA to the eMEA. Culture conditions that may affect assay sensitivity were assessed in experiments 3–5, which examined the effect of group versus individual culture, oxygen concentration, and protein supplementation.

Results

Extended MEA and cell counts identified toxicity not detected by the routine endpoint of blastocyst rate at 96 h. The eMEA was fourfold more sensitive than the standard MEA, and this sensitivity was similar to the morphokinetic MEA. Group culture had a protective effect against toxicity, while oxygen concentration did not affect blastocyst development. Protein supplementation with HSA had a protective effect on blastocyst development in eMEA.

Conclusions

The standard MEA used by manufacturers does not detect potentially lethal toxicity of peroxides in mineral oil. While group culture may mask toxicity, protein supplementation and oxygen concentration have minimal effect on assay sensitivity. The eMEA and time-lapse morphokinetic assessment are equally effective in detection of peroxide toxicity and thus provide manufacturers and end-users a simple process modification that can be readily adopted into an existing QC program.

     

Blastocyst utilization rates after continuous culture in two commercial single-step media: a prospective randomized study with sibling oocytes

Purpose

The aim of this study is to determine whether blastocyst utilization rates are different after continuous culture in two different commercial single-step media.

Methods

This is a paired randomized controlled trial with sibling oocytes conducted in infertility patients, aged ≤40 years with ≥10 oocytes retrieved assigned to blastocyst culture and transfer. Retrieved oocytes were randomly allocated to continuous culture in either Sage one-step medium (Origio) or Continuous Single Culture (CSC) medium (Irvine Scientific) without medium renewal up to day 5 post oocyte retrieval. Main outcome measure was the proportion of embryos suitable for clinical use (utilization rate).

Results

A total of 502 oocytes from 33 women were randomly allocated to continuous culture in either Sage one-step medium (n = 250) or CSC medium (n = 252). Fertilization was performed by either in vitro fertilization or intracytoplasmic sperm injection, and embryo transfers were performed on day 5. Two patients had all blastocysts frozen due to the occurrence of severe ovarian hyperstimulation syndrome. Fertilization and cleavage rates, as well as embryo quality on day 3, were similar in the two media. Blastocyst utilization rates (%, 95% CI) [55.4% (46.4–64.1) vs 54.7% (44.9–64.6), p = 0.717], blastocyst formation rates [53.6% (44.6–62.5) vs 51.9 (42.2–61.6), p = 0.755], and proportion of good quality blastocysts [36.8% (28.1–45.4) vs 36.1% (27.2–45.0), p = 0.850] were similar in Sage one-step and CSC media, respectively.

Conclusions

Continuous culture of embryos in Sage one-step and CSC media is associated with similar blastocyst development and utilization rates. Both single-step media appear to provide adequate support during in vitro preimplantation embryo development. Whether these observations are also valid for other continuous single medium protocols remains to be determined.Clinical trial registration number: NCT02302638.

     

Frozen embryo transfer can be performed in the cycle immediately following the freeze-all cycle

Purpose

In this study, we investigated whether the time interval between oocyte retrieval and frozen embryo transfer (FET) affected the live birth (LB) rates of human segmented-IVF cycles.

Method

A total of 1338 ICSI freeze-all cycles were performed between February 2015 and January 2016, with 1121 FET cycles being retrospectively analyzed. All vitrified-warmed blastocyst transfers were performed in artificial FET cycles, using gonadotropin-releasing hormone (GnRH) agonist downregulation and oral estrogen endometrial preparation. The primary outcome measure was LB. Cycles were investigated in oocyte retrieval-to-FET interval groups of 32–46, 47–61, 62–76, 77–91, and ≥ 92 days, with the 47–61-day group used as the reference group.

Results

There were no significant differences in LB rates between the groups in the overall analysis, as well as, in sub-analyses investigating LB in terms of single blastocyst transfer (SBT), trigger type (GnRH agonist, triggers including hCG), oocyte number (≤ 5 and ≥ 15), and maternal age (> 35 years).

Conclusion

The present study showed that it is feasible to perform transfers 36 days after oocyte retrieval and that delaying FET in freeze-all beyond the cycle immediately following oocyte retrieval does not increase LB rates.

     

Selecting embryos with the highest implantation potential using data mining and decision tree based on classical embryo morphology and morphokinetics

Purpose

The objective of this work was to determine which embryonic morphokinetic parameters up to D3 of in vitro development have predictive value for implantation for the selection of embryos for transfer in clinical practice based upon information generated from embryo transfers with known implantation data (KID).

Methods

A total of 800 KID embryos (100% implantation rate (IR) per transfer and 0% IR per transfer) cultured in an incubator with Time-Lapse system were retrospectively analysed. Of them, 140 embryos implanted, whereas 660 did not.

Results

The analysis of morphokinetic parameters, together with the embryo morphology assessment on D3, enabled us to develop a hierarchical model that places the classical morphological score, the t4 and t8 morphokinetic values, as the variables with the best prognosis of implantation.

Conclusion

In our decision tree, the classical morphological score is the most predictive parameter. Among embryos with better morphological scores, morphokinetics permits deselection of embryos with the lowest implantation potential.

     

Morphokinetic parameters from a time-lapse monitoring system cannot accurately predict the ploidy of embryos

Purpose

This study aimed to test whether there is an association between embryo morphokinetic parameters and ploidy status.

Methods

Patients with high risk of aneuploidy were analyzed by time-lapse microscopy combined with preimplantation genetic screening (PGS). Accordingly, 256 blastocysts from 75 patients were subjected to trophectoderm biopsy and microarray comparative genomic hybridization (array-CGH). Blastocyst development process was analyzed using time-lapse images.

Results

Morphokinetic parameters: tPNf, t2, t3, t4, t5, t8, t9, tcom, tM, tSB, tB, tEB, CC1, CC2, CC3, S2, S3, t5-t2, and tB-tSB showed no significant difference in euploid embryos compared to aneuploid counterparts. In addition, two risk models based on previously published morphokinetic parameters failed to segregate euploid from aneuploid embryos.

Conclusions

Morphokinetic parameters subjected to investigation in the present study failed to improve the chance of selecting euploid embryos.

     

Chromosomal polymorphisms are independently associated with multinucleated embryo formation

Purpose

The purpose of this study is to explore the factors associated with embryo multinucleation, particularly focused on the influence of parental chromosomal polymorphisms in embryo multinucleation.

Methods

This is a retrospective case-control study involving 1260 infertile couples undergoing their first IVF/ICSI cycles. Couples were screened for abnormalities in their karyotype and were evaluated for blastomere persistence of multinucleation. Demographic characteristics, stimulation protocol, and pregnant outcomes were analyzed using logistic regression analysis.

Results

The level of basal FSH was lower in the multinucleated embryos group (5.37 vs 5.72 IU/L). The Multinucleated embryos group received less gonadotropins (1788.5 vs 1891.3 IU), and the level of LH on day of HCG triggering was lower (1.09 vs 1.30 IU/L). More oocytes were recovered in the multinucleated embryos group (11.51 vs 9.23). Chromosomal polymorphisms were seen in at least 1 out of 163 (12.9%) couples. Multivariate logistic regression analysis revealed that chromosomal polymorphisms were independently associated with an increase in the occurrence risk of multinucleated embryos (OR = 1.61, 95% CI, 1.06–2.44) in the first IVF/ICSI cycle. The miscarriage rate in the multinucleated embryos group was 10% higher than that of the control group.

Conclusions

Chromosomal polymorphisms were independently associated with multinucleation embryo formation. A higher LH level on the day of HCG triggering was associated with a decreased chance of multinucleation.

     

Comparison of perinatal outcomes following frozen embryo transfer cycles using autologous versus donor oocytes in women 40 to 43 years old: analysis of SART CORS data

Objective

To study the differences in perinatal outcomes after frozen embryo transfer cycles using autologous or donor oocytes in women of advanced maternal age.

Design

Historical cohort study.

Setting

US national database from the Society of Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) from 2009 to 2013.

Patient(s)

Women at 40–43 years of age undergoing autologous frozen embryo transfers (a-FET) or donor oocyte frozen embryo transfers (d-FET) resulting in singleton pregnancies that were entered in the SART CORS database from 2009 to 2013.

Results

a-FET resulted in 4402 singleton live births whereas d-FET resulted in 2703 singleton live births. d-FET resulted in a higher risk of preterm births (<?37 weeks), with adjusted odds ratio (aOR) 1.33 (95% CI 1.02–1.75), but similar risk of small for gestational age (SGA), with aOR 1.75 (95% CI 0.85–3.7), when compared to a-FET. However, when only single blastocyst transfer cycles are considered, d-FET and a-FET showed no difference in preterm births or other adverse perinatal outcomes.

Conclusions

Singletons resulting from d-FET are at increased risk for perinatal morbidity. However, the risk was diminished in single blastocyst transfer cycles. Our study supports the current American Society for Reproductive Medicine (ASRM) guidelines of transferring a single blastocyst in d-FET cycles.

     

Factors predicting double embryo implantation following double embryo transfer in assisted reproductive technology: implications for elective single embryo transfer

Purpose

The aim of this study was to identify factors associated with double embryo implantation following double embryo transfer (DET) during assisted reproductive technology (ART) procedures and to evaluate the implications of findings in selecting candidates for elective single embryo transfer (eSET).

Methods

Factors predicting double embryo implantation, defined as embryo transfers with two or more heartbeats on 6-week ultrasound following DET, were assessed using the US National ART Surveillance System data from 2000 to 2012 (n?=?1,793,067 fresh, autologous transfers). Adjusted risk ratios (aRRs) were estimated after stratifying by prognosis. Favorable prognosis was defined as first-time ART with supernumerary embryo(s) cryopreserved. Average prognosis was defined as first-time ART without supernumerary embryo(s) cryopreserved, prior unsuccessful ART with supernumerary embryo(s) cryopreserved, or prior ART with previous birth(s) conceived with ART or naturally. Rates and factors associated with double embryo implantation were compared with single embryo implantation following DET among both prognosis groups.

Results

Double embryo implantation was positively associated with blastocyst (versus cleavage) transfer in favorable (aRR?=?1.58 (1.51–1.65)) and average (aRR?=?1.67 (1.60–1.75)) prognosis groups and negatively associated with age >35 years in both prognosis groups. For average prognosis patients, double embryo implantation was associated with retrieving >10 oocytes (aRR?=?1.22 (1.18–1.24)).

Conclusions

Regardless of prognosis, patients aged <35 years with blastocyst-stage embryos and average prognosis patients from whom >10 oocytes were retrieved may be good candidates for eSET. Physicians may consider using these data to counsel patients on eSET, which would reduce multiple gestations and associated complications.

     

The effect of follicle size and homogeneity of follicular development on the morphokinetics of human embryos

Purpose

Our aim was to investigate follicular size (large, ≥17 mm and small, <17 mm) at the time of OPU and homogeneity of follicular development (homogenous development: follicles being present in a homogenous spread of all sizes; heterogeneous: a predominance of small and large follicles) by analysing the morphokinetics of embryo development.

Methods

In this prospective cohort study, 2526 COCs belonging to 187 patients were cultured to day 5. Embryos were evaluated morphokinetically. Four subgroups were defined: large follicles from heterogeneous cycles (LHet) and homogenous cycles (LHom) and small follicles from heterogeneous cycles (SHet) and homogenous cycles (SHom).

Results

Rates of fertilization, blastocyst formation and top and good quality blastocysts were found to be significantly higher in embryos from the LHom group (p < 0.001; p < 0.001; p < 0.001). Small follicles from both homogenous and heterogeneous cycles had significantly lower blastocyst formation and top and good quality blastocyst rates (p < 0.001; p < 0.001). Embryos from SHet had significantly more direct cleavages (p = 0.011). Time to reach blastocyst was shorter in SHom than LHet and LHom (p = 0.002; p = 0.027, respectively). However, once the blastocyst stage was achieved, implantation rates were not significantly different between subgroups, the highest rate being observed in the LHom group. Multivariable analysis revealed that homogeneity of follicular development and follicular size had a significant effect on blastocyst development and quality (p = 0.049; p < 0.001, respectively).

Conclusion

Follicular dynamics, illustrated by follicular size and homogeneity of follicular development, influence early human embryo development. Patterns of follicular growth have an impact on embryo quality and viability which is reflected in morphokinetic variables.

     

Thawed embryo transfer and ectopic pregnancy: a meta-analysis

Purpose

To examine whether thawed embryo transfers can reduce the rate of EP.

Methods

The PubMed, EMBASE, Cochrane Library databases and two randomized controlled trials registration centers were thoroughly searched until March 2017. The clinical outcomes of IVF/ICSI cycles were compared between thawed and fresh embryo transfer.

Results

Twenty-one articles were included in this meta-analysis. There were 801,464 pregnancies totally (thawed-ET: n = 158,967, fresh-ET: n = 642,497). The ectopic pregnancy rate was significantly lower in the group of thawed-ET than that in the group of fresh-ET (OR 0.69, 95% CI 0.57–0.82; I² = 83%). We subdivided the data into subgroups for D3 embryo transfer and D5 embryo transfer. We also found that the ectopic pregnancy rate was significantly lower with thawed-ET on D3 than that with fresh-ET (OR 0.67, 95% CI 0.53–0.85; I² = 0%). The risk of ectopic pregnancy was significantly decreased with thawed-ET on D5 than that with fresh-ET (OR 0.57, 95% CI 0.50–0.64; I² = 45%).

Conclusion

Our results indicate that in contrast to fresh embryo transfers, thawed D3 or D5 embryo transfers can reduce the rate of EP.

     

Improvement of pregnancy outcome by extending embryo culture in IVF-ET during clinical application

Purpose

The purpose of this study is to investigate the application value of the extended embryo culture for 7–8 h in day 3 morning during IVF-ET process.

Methods

Embryos were retrospectively assessed during 08:00–09:00 on the morning of day 3 in the control group, and were assessed once again at 16:00 in the afternoon in the extended culture (EC) group. The embryos with good developmental potential were preferentially selected to transfer. The cumulative pregnancy outcomes were analyzed in one oocyte retrieval cycle.

Results

Similar proportions were found in the rates of cumulative clinical pregnancy, cumulative live birth, and the perinatal/neonatal outcomes per oocyte retrieval cycle (P > 0.05). But higher total clinical pregnancy rate, higher total implantation rate, and lower total abortion rate were obtained in the EC group (P < 0.05). After EC, 53.58% of the embryos were able to continue to develop. The transferred embryos were mainly composed of ≥ 8-cell embryos (75.90%) in the EC group and ≤ 8-cell embryos (82.92%) in the control group. Interestingly, the implantation rates were increasingly improved with the increasing blastomere number up to 56.31% at the morula stage in the EC group, while they were limited to 32.33% at 8-cell stage in the control group.

Conclusions

The extended culture of day 3 embryos for 7–8 h not only reduced the risk of IVF-ET treatment compared to blastocyst culture through another 2–3 days, but also improved the clinical outcomes and the efficiency of every transferred cycle and every transferred embryo.

     

The effects of platelet lysate on maturation,fertilization and embryo development of NMRI mouse oocytes at germinal vesicle stage

Purpose

Improving in vitro maturation could increase the rate of pregnancy from oocytes matured in vitro. Consequently, patients will be prevented from using gonadotropin with its related side effects. In this study, the maturation medium was enriched by platelet lysate (PL), then maturation and subsequent developments were monitored.

Methods

Oocytes at germinal vesicle stage with cumulus cells (cumulus–oocyte complex) and without cumulus cells (denuded oocytes) were obtained from mature female mice. The maturation medium was enriched by 5 and 10 % PL and 5 % PL + 5 % fetal bovine serum (FBS) as experimental groups; the control groups’ media consisted of 5 and 10 % FBS. After 18 h, the matured oocytes were collected and, after fertilization, subsequent development was monitored.

Results

The rates of maturation, fertilization and 2-cell embryo development for the denuded oocyte groups in experimental media 5 % PL and 5 % PL + 5 % FBS were significantly higher than those of the control groups (P < 0.05), while the results for the cumulus–oocyte complex groups were similar between the experimental groups and control groups.

Conclusions

The results of this study indicated that platelet lysate could improve the maturation rate in the absence of granulosa cells compared to media with FBS. This extract also had positive effects on fertilization and embryo development.

     

Bovine in vitro embryo production: the effects of fibroblast growth factor 10 (FGF10)

Purpose

In an attempt to improve in vitro embryo production, we investigated the effect of fibroblast growth factor 10 (FGF10) during in vitro maturation on the developmental capacity of bovine oocytes.

Material and methods

Cumulus–oocyte complexes (COCs) were aspirated from follicles of 3–8 mm diameter. After selection, the COCs were matured in medium with or without 0.5 ng/mL of FGF10. The effect of FGF10 during in vitro maturation (IVM) on nuclear maturation kinetics and expansion of the cumulus cells was investigated. Oocyte competence was assessed by the production and development speed of embryos and the relative expression of genes associated with embryo quality.

Results

FGF10 delayed the resumption of meiosis from 8 h onwards, but did not affect the percentage of oocytes reaching metaphase II, nor did it increase cumulus expansion at 22 h of maturation. We found no difference between treatments regarding embryo production, developmental speed, and gene expression.

Conclusion

In conclusion, the presence of FGF10 during IVM had no effect on embryo production, developmental speed, and gene expression.

     

The association between fatty acid index and in vitro fertilization outcomes

Purpose

Fatty acids have been shown to play an important role in oocyte competence and early implantation of the embryo. Our hypothesis-generating study sought to determine if individual fatty acids expressed as a percentage of total erythrocyte fatty acids are associated with embryo quality and other in vitro fertilization (IVF) outcomes.

Methods

This was a prospective cohort study at an academic fertility center. Sixty women undergoing their first IVF cycle were recruited. Serum measurements of 22 fatty acids were obtained. We calculated each fatty acid as a percentage of total fatty acids, defined as the index for that individual fatty acid.

Results

Omega-3 index had no correlation with IVF outcomes. A negative correlation was found between the trans fatty acid index, elaidic acid (EA), and IVF outcomes, including fertilization rate (r = ? 0.261, p = 0.04), blastocyst conversion rate (r = ? 0.41, p = 0.001), and number of usable blastocysts and embryos (r = ? 0.411, p = 0.001). There was no correlation between EA index and number of oocytes retrieved, embryo grade, or clinical pregnancy. No consistent correlations were observed with the additional fatty acids analyzed.

Conclusions

No correlation was observed between omega-3 index and IVF outcomes. Elevated erythrocyte EA index, the major trans fatty acid commonly consumed in hydrogenated oils, margarine, and fried foods, was negatively correlated with number of usable blastocysts and embryos, blastocyst conversion, and fertilization rate. Our findings suggest preliminary evidence that trans fat may be negatively associated with IVF outcomes.

     

Is early embryo development as observed by time-lapse microscopy dependent on whether fresh or frozen sperm was used for ICSI? A cohort study

Purpose

The aim of this study was to compare timings of key events of embryo development from those originating from either fresh or cryopreserved ejaculate sperm using time-lapse technology.

Methods

In this retrospective observational cohort study, time-lapse technology was used to monitor 1927 embryos from 234 women undergoing intracytoplasmic sperm injection (ICSI) and utilizing either fresh (n = 172 cycles) or cryopreserved ejaculate sperm (n = 62 cycles) for insemination were included in the study. Key developmental events as described in time-lapse were compared with the use of generalized estimating equations (GEE) to adjust for any auto-correlation between the observations. In addition, multivariable logit regression models were used to account for any known baseline differences between the two groups.

Results

There were no differences in conventional embryo development such as number of 8-cell embryos by 72 h (p = 0.359), the number of blastocysts by 120 h (p = 0.417), and the number of top quality blastocysts (p = 0.956) between the two groups compared. There were no statistical differences in the timings of any of the key embryo developmental events (PN_t1, NEBD, cytokinesis, t2, t3, t4, t5, t6, t7, t8, tM, tSB, tEB, tHB, s1, s2, s3, cc2, and cc3) when either fresh or cryopreserved ejaculate sperm was used for ICSI. This was also confirmed with conventional morphological assessment.

Conclusions

This observational cohort study has shown that there are no differences in the morphokinetic parameters of early embryo development when either fresh or frozen ejaculate sperm are used for ICSI insemination.

     

The association between coenzyme Q10 concentrations in follicular fluid with embryo morphokinetics and pregnancy rate in assisted reproductive techniques

Purpose

This study seeks to evaluate the association between follicular fluid (FF) coenzyme Q10 (CoQ10) levels, embryo morphokinetics, and pregnancy rate.

Methods

Sixty infertile patients who underwent intracytoplasmic sperm injection (ICSI) cycles were included in the study. For each patient, CoQ10 level of the follicular fluid was measured by high-performance liquid chromatography system. After the ICSI of each oocyte, the relationship between the level of CoQ10 content of each follicular fluid, the subsequent embryo quality, and embryo morphokinetics was investigated. The relationship between the level of CoQ10 content of each follicle and optimal time-lapse parameters for the embryos of these follicles including t5, s2, and cc2 was also analyzed. The embryos were further classified into four categories, namely, grades A, B, C, and D, according to morphokinetic parameters using t5–t2 and t5–t3 (cc3). Each follicular fluid analysis was performed for a single oocyte of a single embryo which was transferred to the patients. Additionally, follicular fluid CoQ10 levels and pregnancy rates were evaluated.

Results

Follicular fluid CoQ10 levels were significantly higher in grades A and B than grades C and D embryos (p?<?0.05). The concentration of CoQ10 levels was significantly higher in the pregnant group (p?<?0.05). There was no significant correlation between optimal t5 and s2 morphokinetic parameters and CoQ10 levels. However, CoQ10 levels were significantly higher in follicular fluid of embryos which had optimal cc2 (p?<?0.05).

Conclusion

High follicular fluid CoQ10 level is associated with optimal embryo morphokinetic parameters and higher pregnancy rates.

     

Optimal embryo transfer strategy in poor response may include freeze-all

Purpose

In this retrospective cohort study, we investigated the best embryo transfer strategy in ICSI cycles with ≤4 oocytes collected at oocyte retrieval.

Methods

Women who underwent antagonist co-treatment COS for ICSI treatment between January 2010 and December 2015 at a private ART clinic (N?=?2263). Eight hundred seventy-nine women (group 1) had ≤4 oocytes collected at oocyte retrieval, of whom 645 (group A) had cleavage stage embryo transfer (ET), and 234 (group B) had blastocyst ET. One thousand three hundred eighty-four women (group 2) had 10–15 oocytes collected at oocyte retrieval, of whom 676 (group C) had cleavage stage ET, and 708 women (group D) had blastocyst ET. Blastocyst vitrification was performed using the Cryotop method and FET using artificial cycles.

Results

In group 1, the cancellation rate was significantly lower in group A (25.2 vs 38 %). The pregnancy rate (PR), clinical PR, implantation rate (IR), and live birth rate (LBR) per ET and per oocyte retrieval were all lower in group A. The clinical PR, IR, and LBR per ET of vitrified-warmed blastocyst ET were significantly the highest. In group 2, the cycle cancellation rate was significantly lower in group C (3.5 vs 13.4 %). The PR, clinical PR, and IR per ET and per oocyte retrieval were all lower in group C. The LBR per ET was significantly lower, but the LBR per oocyte retrieval was not significantly lower in group C. Again, the PR, clinical PR, and IR per ET of vitrified-warmed blastocyst ET were significantly the highest.

Conclusions

Day 5 ET strategy has been reserved for normal or high responders. The improved pregnancy outcomes from blastocyst culture and cryopreservation may challenge ART to extend this benefit to poor responders.

     

Agonist depot versus OCP programming of frozen embryo transfer: a retrospective analysis of freeze-all cycles

Purpose

In segmented ART treatment or so-called ‘freeze-all’ strategy fresh embryo transfer is deferred, embryos cryopreserved, and the embryo transferred in a subsequent frozen embryo transfer (FET) cycle. The purpose of this cohort study was to compare a GnRHa depot with an oral contraceptive pill (OCP) programming protocol for the scheduling of an artificial cycle FET (AC-FET) after oocyte pick-up (OPU).

Methods

This retrospective cohort study was conducted on prospectively performed segmented ART cycles performed between September 2014 and April 2015. The pregnancy, treatment duration, and cycle cancellation outcomes of 170 OCP programmed AC-FET cycles were compared with 241 GnRHa depot programmed AC-FET cycles.

Results

No significant difference was observed in the per transfer pregnancy and clinical pregnancy rates between the OCP and GnRHa groups, 72.0 versus 77.2 %, and 57.8 versus 64.3 %, respectively. Furthermore, the early pregnancy loss rate was non-significantly different between the OCP and GnRH protocol groups, 19.8 versus 16.7 %, respectively. However, nine (5.29 %) cycles were cancelled due to high progesterone in the OCP protocol group, while no cycles were cancelled in the GnRHa protocol group and the time taken between OPU and FET was 19 days longer (54.7 vs 35.6 days) in the OCP protocol compared to the GnRHa protocol.

Conclusions

The results of this AC-FET programming study suggests that the inclusion of GnRHa depot cycle programming into a segmented ART treatment will ensure pregnancy, while significantly reducing treatment duration and cycle cancellation.

     

Effect of embryo and blastocyst transfer on the birthweight of live-born singletons from FET cycles

Purpose

To evaluate the effect of culture duration (embryo (day 3) transfer vs. blastocyst (day 5–6) transfer) on the birthweight of singletons from frozen embryo transfer (FET) cycles.

Methods

A total of 1092 singletons were analyzed in this retrospective study. The distribution of large for gestational age (LGA) infants, the mean birthweight, and z scores of singletons were compared between the day 3 and day 5–6 transfer groups. Multiple linear regression analysis was performed to evaluate the relationships between confounding factors and singleton birthweight.

Results

The proportion of LGA infants significantly increased with BMI (BMI?<?20, 12.8%; 20?≤?BMI?≤?25, 23.2%; BMI?>?25, 32.3%; P?<?0.0001). However, the proportions of small for gestational age (SGA) and LGA infants were not significantly different between day 3 and day 5–6 transfers. The absolute mean birthweight of singletons was not significantly different between day 3 transfer (3422?±?547 g) and day 5–6 transfer (3433?±?559 g; P?=?0.732). The z scores (calculated from a reference population) of singletons were also not significantly different between the two groups (0.499 vs. 0.533, P?=?0.625). Multiple linear regression analysis showed that maternal BMI, gestational age, and infant gender had significant effects on singleton birthweight, while culture duration (P?=?0.731) did not significantly affect singleton birthweight.

Conclusions

In vitro culture duration did not affect the birthweight of newborns resulting from day 3 to day 5–6 transfers in FET cycles.

     

Closed vitrification of human oocytes and blastocysts: outcomes from a series of clinical cases

Purpose

High survival rates and clinical outcomes similar to those from fresh oocytes and blastocysts have been observed with open oocyte vitrification systems. It has been suggested that the extremely fast cooling rates that are only achieved with open systems are necessary for human oocyte and blastocyst vitrification. However, there is a potential risk of introducing contamination with open systems. The aim of this study was to assess whether similar survival and subsequent implantation rates could be achieved using a closed vitrification system for human oocytes and blastocysts.

Methods

Initially, donated immature oocytes that were matured in vitro were vitrified using the cryoprotectants ethylene glycol (EG) + dimethyl sulphoxide (DMSO) + sucrose and either a closed system (Rapid-i®) or an open system (Cryolock). The closed system was subsequently introduced clinically for mature oocyte cryopreservation cases and blastocyst vitrification.

Results

Using in vitro matured oocytes, a similar survival was achieved with the open system of 92.4 % (73/79) and with the closed system of 89.7 % (35/39). For clinical oocyte closed vitrification, high survival rate of 90.5 % (374/413) and an implantation rate of 32.7 % (18/55) from the transfer of day 2 embryos was achieved, which is similar to fresh day 2 embryo transfers. Blastocysts have also been successfully cryopreserved using the Rapid-i closed vitrification system with 94 % of blastocysts having an estimated ≥75 % of cells intact and a similar implantation rate (31.5 %) to fresh single blastocyst transfers.

Conclusion

Closed vitrification can achieve high survival and similar implantation rates to fresh for both oocytes and blastocysts.