A Review of The Society for Assisted Reproductive Technology Embryo Grading System and Proposed Modification

Non invasive assessment of human oocytes and embryos in assisted reproduction: Review on present practices and future trends

Oocyte and embryo grading is one of the most important steps in assisted reproductive technology to identify the best among cultured embryos for transfer or vitrification. The most commonly used non-invasive method is morphological assessment of gametes and embryos using a microscope. This method despite being simple and cost-effective has interobserver and intraobserver variability and subjectivity and has little to offer about the physiological state of embryos. This review sourced research articles and reviews pertaining to other non-invasive assessment methodologies from Medline and PubMed to collate latest technologies in vogue and identify novel methodologies of the future. The review assesses the current understanding in oocyte and embryo grading and touches upon novel non-invasive techniques and potential biomarkers to identify the best embryo. The latest available literature on time-lapse imaging, hierarchical algorithms, omics (consisting of proteomics and secretomes), miRNAs, mitochondrial RNAs and artificial intelligence has been accessed to summarize the enormous information available, to identify gaps in current interpretations, to identify emerging technologies and to provide direction for future research. This review will greatly benefit anyone practicing assisted reproduction and clinical embryology.

Effects of multiple doses of gonadotropin-releasing hormone agonist on the luteal-phase support in assisted reproductive cycles: A clinical trial study

Background

The effect of adding gonadotropin-releasing hormone (GnRH) agonist on the luteal phase support in assisted reproductive technique (ART) cycles is controversial.

Objective

To determine the effects of adding multiple doses of GnRH agonist to the routine luteal phase support on ART cycle outcomes.

Materials and Methods

This clinical trial study included 200 participants who underwent the antagonist protocol at the Research and Clinical Center for Infertility, Yazd, Iran, between January and March 2020. Of the 200, 168 cases who met the inclusion criteria were equally divided into two groups - the case and the control groups. Both groups received progesterone in the luteal phase, following which the case group received GnRH agonist subcutaneously (0/1 mg triptorelin) zero, three, and six days after the fresh embryo transfer, while the control group did not receive anything. Finally, chemical and clinical pregnancy rates, number of mature oocytes, fertilization rate, total dose of gonadotropin, and the estradiol level were determined.

Results

The baseline characteristics were similar in both groups. No significant difference was observed between embryo transfer cycles. Clinical results showed that differences between the fertilization rate, chemical and clinical pregnancies were not significant.

Conclusion

The results showed that receiving multiple doses of GnRH agonist in the luteal phase of ART cycles neither improves embryo implantation nor the pregnancy rates; therefore, further studies are required.

In vitro maturation with letrozole priming: Can it be a solution for patients with cancerophobia? A pilot study

Objective:

To investigate whether letrozole priming could be used efficiently in patients undergoing in vitro maturation (IVM) as compared with follicle-stimulating hormone (FSH) priming.

Materials and Methods:

This is a retrospective analysis of 63 patients who underwent IVM due to the high risk of Ovarian Hyperstimulation syndrome (OHSS) (n=39), cancerophobia (n=16), and desire for IVM after failed in vitro fertilization attempts (n=8). Forty-two patients received FSH priming and 21 patients received letrozole priming.

Results:

The patients who had FSH or letrozole priming were statistically similar with respect to age, body mass index, duration of infertility, basal antral follicle count, serum anti-Müllerian hormone levels, and IVM indications (p>0.05 for all). When compared with the FSH priming group, the number of germinal vesicle oocytes, metaphase II and fertilized oocytes were significantly higher (p=0.003, p=0.001, and p=0.016, respectively), but the number of metaphase I oocytes was significantly lower in the letrozole priming group (p=0.002). The patients who received FSH and letrozole priming had statistically similar rates of implantation (33.3% vs 37.0%, p=0.709), clinical pregnancy (31.5% vs 33.3%, p=0.848), twinning (1.9% vs 3.7%, p=0.611), and live birth (24.1% vs 29.6%, p=0.682).

Conclusion:

Potential indications for IVM include patients with increased risk for OHSS and contraindication for hyperestrogenism. Aromatase inhibitors can be used to preserve the fertility of patients with estrogen-sensitive cancers. Letrozole priming appears to be an efficient approach in patients who undergo IVM, with likely less cost than FSH priming.

Blastocyst classification systems used in Latin America: is a consensus possible?

OBJECTIVE

To identify different blastocyst classification systems used by embryologists in Latin American countries and evaluate the possibility of establishing a consensus among these countries.

METHODS

An E-mail survey was carried out through the Latin American Network of Assisted Reproduction (REDLARA) aimed at embryologists from assisted reproduction centers in Latin countries.

RESULTS

Sixty surveys were collected from 12 Latin American countries, of which 66.7% had >10years of professional practice as embryologists. Seven different blastocyst classification systems were reported, of which 5 have previously been described in the literature.

CONCLUSION

Although the group of embryologists surveyed use different blastocyst classification systems, most in this group consider that the embryo score system should be unified in their countries as well as in the region.