P–266 Morphometric assessment of Ratio of inner-cell-mass diameter to blastocyst diameter is an effective criterion to select best embryo for successful outcomes in single blastocyst transfer-cycles

Study question

Can semi-quantitative measurement of ICM diameter vis-à-vis blastocyst diameter, calculated from photographic images, be a significant predictor of implantation potential in single blastocyst transfer cycles?

Summary answer

A simple, non-invasive measurement of ICM:Blastocyst diameter ratio is a potentially effective predictor of high developmental potential, implantation, live-birth rates in single blastocyst transfer cycles. What is known already: Correlationship between quantitative measurements of blastocyst morphology such as size and shape of ICM and its implantation potential were first reported by Richter et al. Widely used Gardner and Schoolcraft’s qualitative scoring assessment is based on three major variables: expansion stage of blastocyst, cohesiveness of the inner cell mass (ICM), and consistency of trophectodermal (TE) cells. A top quality single blastocyst transfer yields implantation rate nearing 70% and live-birth rate about 50%. If an additional morphological but vital parameter evaluating ICM:Blastocyst diameter ratio is introduced to the Gardner’s blastocyst gradation system, it may help enhance IVF success rates still further.

Study design, size, duration

A prospective observational cohort study of women (n = 244) undergoing IVF treatment at our private fertility clinic from April 2018 until March 2020.

Women with their autologous fertilized oocytes undergoing extended culture and transfer of a single fresh, at least fully expanded (Grade 3) blastocyst with a measurable ICM diameter and blastocyst inner diameter on day 5/6, irrespective of age, cycle number and indication for treatment, were included. Cryopreservation cycles were excluded.

Participants/materials, setting, methods

Each blastocyst was evaluated for expansion grade, ICM and TE according to Gardner et al. conventional method. Additionally, ratio of ICM diameter w.r.t. blastocyst inner diameter was also calculated from the photographic images on screen using the Hamilton-Thorne software package embedded with their laser system. Measurements were done on blastocysts where expansion had occurred between 114 and 120 hours after insemination. Implantation rates and live-birth rates were the major end-points.

Main results and the role of chance

A total of 244 blastocyst transfers were performed in same number of women, and 130 clinical pregnancies were achieved (53.3%). The average age of the women was 32.5 ± 4.2 years. The blastocysts that implanted successfully had an average ICM:blastocyst diameter ratio of 0. 469±0.082), whereas blastocysts that did not implant had a significantly lower ratio of 0.325±0.09 (P <.0001). No statistical significant difference was found in the TE grade between the blastocysts that implanted successfully and those that did not. Out of the 130 pregnancies achieved, 89 (68%) resulted in the delivery of a healthy baby. After ROC analysis, a cutoff value for the ICM/blastocyst ratio showed equal rank for sensitivity (0.81) and specificity (0.72). The resultant positive predictive value was 78%, and the negative predictive value was 74%. In our study, the conditional probability of achieving pregnancy upon transfer of a single blastocyst with an ICM:blastocyst ratio higher than the cutoff value of 0.4255 was 76%. This was significantly higher than the probability of pregnancy from blastocysts graded by conventional morphometry.

Limitations, reasons for caution

Our study is limited by the small sample size. Hence more multicentric studies are warranted to observe similar conclusion. Wider implications of the findings: The strengths of the study are the performance of single blastocyst transfers and using live births as the measurement endpoint. It is important to mention that embryo grading is inevitably subject to intra- and interobserver variations. However, with simple measurements of image data recording eliminates a degree of these variations.

Trial registration number

Not applicable

Follicular fluid dehydroepiandrosterone sulfate is a credible marker of oocyte maturity and pregnancy outcome in conventional in vitro fertilization cycles

AIM:

To investigate if the level of dehydroepiandrosterone sulfate (DHEA-s) in follicular fluid (FF) influences the competence of oocytes to fertilize, develop to the blastocyst stage, and produce a viable pregnancy in conventional in vitro fertilization (IVF) cycles.

SETTINGS AND DESIGN:

Prospective study of age-matched, nonpolycystic ovary syndrome (PCOS) women undergoing antagonist stimulation protocol involving conventional insemination and day 5 blastocyst transfer.

MATERIALS AND METHODS:

FF levels of DHEA-s and E2 were measured by a radio-immuno-assay method using diagnostic kits. Fertilization rate, embryo development to the blastocyst stage and live birth rate were main outcome measures. Cycles were divided into pregnant/nonpregnant groups and also into low/medium/high FF DHEA-s groups. Statistical analysis was done by GraphPad Prism V software.

RESULTS:

FF DHEA-s levels were significantly higher in pregnant (n = 111) compared to nonpregnant (n = 381) group (1599 ± 77.45 vs. 1372 ± 40.47 ng/ml; P = 0.01). High (n = 134) FF DHEA-s group had significantly higher percentage of metaphase II (MII) oocytes (91.5 vs. 85.54 vs. 79.44%, P < 0.0001), fertilization rate (78.86 vs. 74.16 vs. 71.26%, P < 0.0001), cleavage rate (83.67 vs. 69.1 vs. 66.17%, P = 0.0002), blastocyst formation rate (37.15 vs. 33.01 vs. 26.95%, P < 0.0001), and live birth rate (29.85 vs. 22.22 vs. 14.78%, P = 0.017) compared to medium (n = 243) and low (n = 115) FF DHEA-s groups, respectively despite comparable number of oocytes retrieved and number of blastocysts transferred. FF DHEA-s levels correlated significantly with the attainment of MII oocytes (Pearson r = 0.41) and fertilization rates (Pearson r = 0.35).

CONCLUSION:

FF DHEA-s level influences the oocyte maturation process and is predictive of fertilization, embryo development to the blastocyst stage and live birth rates in non-PCOS women undergoing conventional IVF cycles.

Transfer of spontaneously hatching or hatched blastocyst yields better pregnancy rates than expanded blastocyst transfer

CONTEXT:

Blastocyst stage embryo transfer (ET) has become routine practice in recent years. However, probably due to limitations of assisted hatching techniques, expanded blastocyst transfer (EBT) is still the preferred mode. Inexplicably, not much consideration has been given to spontaneously hatching/hatched blastocyst transfer (SHBT).

AIM:

This study aimed to investigate developmental potential of spontaneously hatching/hatched blastocyst against EBT in in vitro fertilization (IVF) cycles.

SETTINGS AND DESIGN:

Prospective study of 146 women undergoing their first IVF- ET cycle.

SUBJECTS AND METHODS:

On the basis of blastocyst status, women were classified into SHBT and EBT groups. Intracytoplasmic sperm injection cycles were excluded to remove male factor bias. Implantation rate (IR), clinical pregnancy rate, and live birth rate were the main outcome measures.

STATISTICAL ANALYSIS:

Graph-pad Prism 5 statistical package.

RESULTS:

SHBT group showed significantly higher blastocyst formation rate (53.3 ± 17.5 vs. 43.1 ± 14.5%, P = 0.0098), top-quality blastocysts (71.8 vs. 53.7%, P = 0.0436), IR (43.6 vs. 27.9%, P = 0.0408), pregnancy rate (59.4 vs. 45.1%, P = 0.0173), and live birth rate (36.8 vs. 22.8%, P = 0.003) compared to EBT group. Multiple pregnancy rates remained comparable between the two groups. Implantation correlated strongly with top-quality blastocysts (Pearson, r = 0.4441) in SHBT group, while the correlation was nonsignificant in EBT group.

CONCLUSION:

Extending culture of expanded blastocysts by a few hours to allow transfer of spontaneously hatching/hatched blastocysts gives higher implantation and pregnancy rates with no added risk of multiple gestations. Spontaneously hatching/hatched blastocysts have a better potential to implant and develop into a positive pregnancy.

Follicular-fluid anti-Mullerian hormone (FF AMH) is a plausible biochemical indicator of functional viability of oocyte in conventional in vitro fertilization (IVF) cycles

CONTEXT

Oocyte quality may be a governing factor in influencing in vitro fertilization (IVF) outcomes. However, morphological evaluation of oocyte quality is difficult in conventional IVF cycles. Follicular-fluid (FF), the site for oocyte growth and development, has not yet been sufficiently explored to obtain a marker indicative of oocyte quality. Anti-Mullerian hormone (AMH) is produced by granulosa cells of preantral and early-antral follicles and is released in FF.

AIM

To investigate AMH as a biochemical indicator of functional viability/quality of oocyte produced in the FF micro-environmental milieu.

SETTINGS AND DESIGN

Prospective study involving 132 cycles of conventional IVF-embryo transfer (ET) in infertile women.

SUBJECTS AND METHODS

AMH concentration was estimated in pooled FF on day of oocyte pickup. Cycles were sorted into low and high groups according to median (50 (th) centile) values of measurement. Main outcome measure was oocyte viability, which included morphological assessment of oocyte quality, fertilization rate, clinical pregnancy, and implantation rates.

STATISTICAL ANALYSIS

Graph-pad Prism 5 statistical package.

RESULTS

Low FF AMH group shows significantly higher percentage of top-quality oocytes (65.08 ± 24.88 vs. 50.18 ± 25.01%, P =0.0126), fertilization (83.65 ± 18.38 vs. 75.78 ± 21.02%, P =0.0171), clinical pregnancy (57.57 vs. 16.67%, P >0.0001), and embryo implantation rates (29.79 vs. 7.69%, P >0.0001) compared to high FF AMH group. FF AMH shares an inverse correlation with FF E2 (Pearson r = -0.43, r(2) = 0.18) and clinical pregnancy (Pearson r = -0.46, r(2) = 0.21). Threshold value of FF AMH for pregnancy is >1.750 ng/mg protein.

CONCLUSION

FF AMH is a plausible biochemical indicator of functional viability of oocyte in conventional IVF cycles.

Follicular fluid insulin like growth factor-1 (FF IGF-1) is a biochemical marker of embryo quality and implantation rates in in vitro fertilization cycles

CONTEXT:

Insulin-like growth factor-1 (IGF-1) has been reported to play a role in human follicular and embryonic development. However, earlier studies carried out mostly in animal models or in culture mediums supplemented with IGF-1 have been unable to directly link IGF-1 with embryo quality. Results correlating IGF-1 with pregnancy outcome have also been ambiguous so far.

AIM:

The aim of this study is to find if in situ follicular-fluid level of IGF-1 is predictive of embryo quality and implantation rates in in vitro fertilization (IVF) cycles.

SETTINGS AND DESIGN:

Prospective study involving 120 cycles of conventional IVF-embryo transfer in infertile women.

SUBJECTS AND METHODS:

IGF-1 concentrations were estimated in pooled follicular-fluid on the day of oocyte-pickup. Embryo quality was assessed daily at different developmental stages. Cycles were sorted into low and high follicular fluid insulin-like growth factor-1 (FF IGF-1) groups according to the median value of measurement. Embryo quality, clinical pregnancy and implantation rate were the main outcome measures.

STATISTICAL ANALYSIS:

Graph-pad Prism 5 statistical package.

RESULTS:

FF IGF-1 correlates with embryo quality (Pearson r = 0.3894, r² = 0.1516, P > 0.0001) and clinical pregnancy (Pearson r = 0.5972, r² = 0.36, P > 0.0001). High FF IGF-1 group shows significantly higher rates of fertilization, cleavage, blastocyst formation and top grade embryos compared with low FF IGF-1 group. Clinical pregnancy rates (38.33 vs. 20%, P = 0.0272) and embryo implantation rates (21.6 vs. 10.32%, P = 0.0152) are also significantly higher in the high versus low FF IGF-1 group. Threshold value of FF IGF-1 for clinical pregnancy is <58.50 ng/mg protein (receiver operating characteristics _AUC : 0.85 ± 0.03, 95% CI: 0.78-0.91).

CONCLUSION:

FF IGF-1 is a plausible biochemical marker of embryo quality and implantation rate and correlates with clinical pregnancy rates in conventional IVF cycles.