Comparison of IVF and IVM outcomes in the same patient treated with a modified IVM protocol along with an oocytes-maturing system containing melatonin: A pilot study.

AIM: To compare embryonic developmental competence and clinical outcomes of oocytes matured in vivo (IVF oocytes) and those matured in vitro (IVM oocytes) from the same IVM/IVF cycles, and to analyze the clinical efficiency of a melatonin-supplemented in vitro maturation system combined with a modified IVM/IVF protocol. MAIN METHODS: We randomly recruited 22 patients undergoing IVM/IVF treatment protocol in our medical centre. The fertilization, cleavage and blastocyst formation rates, as well as clinical pregnancy, implantation and live birth/ongoing pregnancy rates were analysed and compared between IVF and IVM oocytes. We evaluated mitochondrial function indicators by fluorescence staining and confocal microscopy, including mitochondrial membrane potential, reactive oxygen species and calcium (Ca2+) levels in 15 IVF and 15 IVM oocytes. KEY FINDINGS: There were no significant differences in fertilization or blastocyst formation rates between the IVF and IVM groups, whereas the cleavage rate was significantly higher in the IVF versus IVM group (100% vs 93.4 ± 10.9%, p = 0.03). There were no significant differences in the clinical pregnancy, implantation or live birth/ongoing pregnancy rates between the two groups. The cumulative clinical pregnancy and ongoing pregnancy/live birth rate per pick-up oocyte in the IVM/IVF treatment cycles were 68.2% (15/22) and 54.5% (12/22), respectively. The reactive oxygen species and Ca2+ levels were significantly increased, and mitochondrial membrane potential was significantly decreased, in IVM compared with IVF oocytes. SIGNIFICANCE: The modified IVM/IVF protocol can be effectively applied to the treatment of some indicated patients and achieve ideal clinical outcomes, even though the developmental potential of IVM oocytes may not be as high as IVF oocytes.

Association between mild stimulated IVF/M cycle and early embryo arrest in sub fertile women with/without PCOS.

BACKGROUND: The in vitro maturation (IVM) technique has physical and financial benefits, but a lower efficiency and outcome that is still unclear whether it is related to polycystic ovary syndrome (PCOS) itself or the IVM procedure. In this study, we analyzed the clinical and laboratory outcomes of an optimized IVM protocol in patients with and without PCOS. We also discussed the possible reasons for early embryo arrest in the IVM cycle. METHODS: This prospective study involved 58 PCOS patients and 56 non-PCOS patients who underwent mild stimulated IVF combined IVM (IVF/M) cycles. The clinical and laboratory outcomes were compared between the two groups. Also, metaphase II (MII) oocytes were obtained after IVM from the two groups, and in vivo MII oocytes randomly collected from IVF patients were examined for mitochondrial function using a laser scanning confocal microscope (LSCM). The aneuploidy rate for arrested cleavage embryos from IVM and IVF oocytes were screened using Next Generation Sequencing (NGS). RESULTS: Mildly stimulated IVF/M resulted in cumulative clinical pregnancy and implantation rates (40.2, 28.7% in the PCOS group vs. 41.9, 36% in the non-PCOS group), respectively. The blastocyst formation rates were comparable (28% vs. 28.2%) in PCOS and non-PCOS groups, respectively. Using LSCM, there was a significant decrease in the mitochondrial membrane potential of IVM oocytes compared with the control IVF oocytes (P < 0.001), but no significant difference between the PCOS and non-PCOS groups. The NGS showed that the aneuploidy rates were comparable (75, 75, and 66.6%) in IVM-PCOS, IVM-non-PCOS, and control IVF arrested embryos, respectively. CONCLUSIONS: The mildly stimulated IVF/M protocol produced acceptable clinical outcomes in PCOS and non-PCOS patients. IVM itself rather than the PCOS condition adversely affected the embryo development through its effect on mitochondrial function, which appeared to be a possible cause for the embryo arrest in the IVM cycles rather than chromosomal aneuploidy.

A novel hemizygous loss-of-function mutation in ADGRG2 causes male infertility with congenital bilateral absence of the vas deferens.

PURPOSE: Cystic fibrosis transmembrane conductance regulator (CFTR) and adhesion G protein-coupled receptor G2 (ADGRG2) have been identified as the main pathogenic genes in congenital bilateral absence of the vas deferens (CBAVD), which is an important cause of obstructive azoospermia. This study aimed to identify the disease-causing gene in two brothers with CBAVD from a Chinese consanguineous family and reveal the intracytoplasmic sperm injection (ICSI) outcomes in these patients. METHODS: Whole-exome sequencing and Sanger sequencing were used to identify the candidate pathogenic genes. Real-time polymerase chain reaction, immunohistochemistry, and immunofluorescence were used to assess the expression of the mutant gene. Moreover, the ICSI results from both patients were retrospectively reviewed. RESULTS: A novel hemizygous loss-of-function mutation (c.G118T: p.Glu40*) in ADGRG2 was identified in both patients with CBAVD. This mutation is absent from the human genome databases and causes an early translational termination in the third exon of ADGRG2. Expression analyses showed that both the ADGRG2 mRNA and the corresponding protein were undetectable in the proximal epididymal tissue of ADGRG2-mutated patients. ADGRG2 expression was restricted to the apical membranes of non-ciliated epithelia in human efferent ducts, which was consistent with a previous report in mice. Both ADGRG2-mutated patients had normal spermatogenesis and had successful clinical outcomes following ICSI. CONCLUSIONS: Our study verifies the pathogenic role of ADGRG2 in X-linked CBAVD and broadens the spectrum of ADGRG2 mutations. In addition, we found positive ICSI outcomes in the two ADGRG2-mutated CBAVD patients.

The mechanisms and clinical application of mosaicism in preimplantation embryos.

Embryos containing distinct cell lines are referred to as mosaic embryos, which are considered to be caused by mitotic errors in chromosome segregation during preimplantation development. As the accuracy and resolution of detection techniques improve, more and more mosaic embryos were identified recently. The impacts of mosaic embryos on survival and potential pregnancy outcome have been reported to be diverse in different studies. Because of the universality and clinical significance of mosaicism, it is essential to unravel the mechanisms and consequences with regard to this phenomenon in human pre- and post-implantation embryos. The purpose of this review is to explore the mechanisms, causes of mosaicism, and the development of pre- and post-implantation mosaic embryos in the light of recent emerging data, with the aim of providing new references for clinical applications.