Table 4. Oocyte quality biomarkers in embryo assessment: a summary of review results for oocyte evaluation in assisted reproductive technologies.
Study Study design Time of assessment Developmental quality predictor Developmental stage grading Main outcomes p-value
Carpintero et al. (2014) Prospective cohort D3 Estradiol; progesterone; testosterone Ardoy et al. (2008) Embryo qualities A and C, and B and C, differed in the estradiol/progesterone ratio; 0.003, 0.0009
Embryo qualities B and C differed in the estradiol/testosterone ratio 0.001
Wirleitneret al. (2018) Prospective cohort D5 Follicle size Gardner et al. (2000) Blastocyst rates were lower in small than in medium follicles, both per aspirated follicle (15.3% vs 27.9%) and Per COC (24.0% vs 36.4%); <0.05 Both
The rate of top-quality blastocysts was 12.1% in small, 19.4% in medium and 14.3% in large follicles NS
Fu et al. (2018) Case-control D5 MIR-663B Top-scoring: blastocysts with good ICM and TE assessed as A or B (≥3BB); poor-scoring: blastocysts with few and large cells for ICM or TE assessed as C (<3BB) Expression levels of FF MIR-663B for top-scoring embryos were lower than that of poor scoring 0.003
Latif Khanet al. (2020) Prospective cohort D3 cfDNA; melatonin Morphological criteria: i) cleavage rate and the number of blastomeres, ii) cytoplasmic appearance, iii) extent of fragmentation, iv) regularity in the symmetry of blastomeres cfDNA was lower in FF related to oocytes that produced topquality embryos compared to low quality embryos <0.001,
In non-pregnant women, oocytes from FF with lower melatonin levels resulted in embryos with higher fragmentation rates < 0.001
McCullohet al. (2020) Prospective cohort D5; D6 Follicle size Gardner et al. (2000) Quality blastocysts were found to have an association with larger follicles 0.01
Scarica et al. (2019) Prospective exploratory Before TE biopsy PTGS2; CAMK1D; HAS2 Gardner & Schoolcraft (1999) CAMK1D, PTGS2, and HAS2 were more highly expressed in GC of oocytes that resulted in embryos reaching the blastocyst stage than in those that experienced developmental arrest 0.01, 0.05, 0.03, resp.
Shen et al. (2020) Prospective observational D3 VCAN Gardner & Sakkas (2003) VCAN was positively correlated to embryo grade 0.024
Uppangala et al. (2020) Prospective cohort D3 E2; MDA Morphological criteria: grade I corresponded to stage-specific cell number, uniform blastomere size, without multinucleation, and no or <10%fragmentation Patients with normal ovarian response and serum E2 between 2000-3000 pg/mL had77.03 % grade Iembryos; <0.01 both
Patients with lower and higher levels had 40.74% and 51.88% compared to normal, resp. < 0.01
Yi et al. (2020) Prospective cohort D3 Prdx4; SOD Good quality embryos contained at least 7 cells and with ≤ 10% of fragmentation Prdx4 and SOD levels were positively correlated with good quality embryo rate 0.013, 0.021
Yuan et al. (2021) Prospective experimental T2; t4; t8; D5; D6 LINE; LTRs Not specified DNA methylation in LINE (including L1, L2) and LTR was higher in PBIs of embryos that could not reach the blastocyst stage <0.05
Zhang et al. (2021a) Prospective observational D3; D5 miR-103a-3p; miR-10a-5p Good quality embryos developed from normal fertilized eggs with no or ≤ 1/3 fragmentation miR-103a-3p and miR-10a-5p expression levels were increased in the subgroups in which oocytes did not develop into high-quality embryos on D3 or D5 D3: 0.05, 0.01, resp.D5: 0.05 both
Yu et al. (2022) Prospective cohort D3;D5 LH;FSH; cortisone High-quality embryos had 8 symmetrical, non-fragmented blastomeres on D3, and showed the development of ICM, the appearance of the TE, and the expansion of the blastocyst on D5 FF LH, FSH, and cortisone were strong predictors of top-quality embryos on D5 0.037, 0.014, 0.04,resp.
Machtingeret al. (2023) Prospective cohort D3 r-hCG; GnRH-a Top-quality embryo contained 7-8 equal blastomeres and ≤10% of fragmentation There was no significant difference in the number of top-quality embryos between the r-hCG and GnRH-a stimulation protocol groups NS

CAMK1D: calcium/calmodulin-dependent protein kinase ID; cfDNA: cell-free DNA; COC: cumulus-oocyte complex; D2: day 2; D3: day 3; D5: day 5; D6: day 6; E2: estradiol; FF: follicular fluid; FSH: follicle stimulating hormone; GC: granulosa cells; GnRH-a: gonadotropin-releasing hormone GnRH agonist; HAS2: hyaluronan synthase 2; ICM: inner cell mass; LH: luteinizing hormone; LINE: long interspersed nuclear element; L1: LINEI; L2: LINE2; LTR: long terminal repeats; MDA: malondialdehyde; MIR-663b: microRNA-663B; NS: not significant; PBI: polar body I; Prdx4: peroxiredoxin 4; PTGS2: prostaglandin-endoperoxide synthase 2; r-hCG: recombinant human chorionic gonadotropin; SOD: superoxide dismutase; TE: trophectoderm; t2: two-cell stage; t4: four-cell stage; t8: eight-cell stage; VCAN: versican.