What are the genetic causes of total fertilization failure (TFF) in a proband suffering from male infertility? Novel compound heterozygous variants (c.[463C>T];[1084G>A], p.[(Arg155Ter)];[(Gly362Arg)]) in actin-like protein 7A (ACTL7A) were identified as a causative genetic factor for human TFF. ACTL7A, an actin-related protein, is essential for spermatogenesis. ACTL7A variants have been reported to cause early embryonic arrest in humans but have not been studied in human TFF. We recruited a non-consanguineous family whose son was affected by infertility characterized by TFF after ICSI. Whole-exome sequencing was used to identify the potential pathogenic variants. Artificial oocyte activation (AOA) after ICSI was performed to overcome TFF and any resulting pregnancy was followed up. Sanger sequencing was performed to validate the variants. Pathogenicity of the identified variants was predicted by in silico tools. The ultrastructure of spermatozoa was studied by transmission electron microscopy (TEM). Immunofluorescence staining and western blotting were used to investigate the mechanism of the variants on the affected spermatozoa. Novel compound heterozygous variants in ACTL7A (c.[463C>T];[1084G>A], p.[(Arg155Ter)];[(Gly362Arg)]) were identified in a family with TFF after ICSI. In silico analysis predicted that the variants lead to a disease-causing protein. TEM showed that the ACTL7A variants caused ultrastructural defects in the acrosome and perinuclear theca. Protein expression of ACTL7A and phospholipase C zeta, a key sperm-borne oocyte activation factor, was significantly reduced in the affected sperm compared to healthy controls, suggesting that the ACLT7A variants lead to an oocyte activation deficiency and TFF. AOA by calcium ionophore (A23187) after ICSI successfully rescued the TFF and achieved a live birth for the patient with ACTL7A variants. Given the rarity of sperm-associated TFF, only one family with an only child carrying the ACTL7A variants was found. In addition, the TFF phenotype was not assessed in two or more ICSI cycles, due to the intervention in ICSI with AOA after one failed ICSI cycle. Further studies should validate the ACTL7A variants and its effect on male infertility in larger independent cohorts. : Our findings revealed a critical role of ACTL7A in male fertility and identified bi-allelic variants in ACTL7A associated with human TFF, which expands the genetic spectrum of TFF and supports the genetic diagnosis of TFF patients. We also rescued TFF by AOA and obtained a healthy live birth, which provides a potentially effective intervention for patients with ACTL7A pathogenic variants. This work was supported by the National Natural Science Foundation of China (81971374 and 81401267). No conflicts of interest were declared. N/A.

In this multicenter, non-inferiority, randomized trial, we randomly assigned 992 women undergoing in-vitro fertilization (IVF) with a good prognosis (aged 20-40, ≥3 transferrable cleavage-stage embryos) to strategies of blastocyst-stage (n = 497) or cleavage-stage (n = 495) single embryo transfer. Primary outcome was cumulative live-birth rate after up to three transfers. Secondary outcomes were cumulative live-births after all embryo transfers within 1 year of randomization, pregnancy outcomes, obstetric-perinatal complications, and livebirths outcomes. Live-birth rates were 74.8% in blastocyst-stage group versus 66.3% in cleavage-stage group (relative risk 1.13, 95%CI:1.04-1.22; P_{non-inferiority} < 0.001, P_superiority = 0.003) (1-year cumulative live birth rates of 75.7% versus 68.9%). Blastocyst transfer increased the risk of spontaneous preterm birth (4.6% vs 2.0%; P = 0.02) and neonatal hospitalization >3 days. Among good prognosis women, a strategy of single blastocyst transfer increases cumulative live-birth rates over single cleavage-stage transfer. Blastocyst transfer resulted in higher preterm birth rates. This information should be used to counsel patients on their choice between cleavage-stage and blastocyst-stage transfer (NCT03152643, https://clinicaltrials.gov/study/NCT03152643).

This study aimed to investigate the role of low-density lipoprotein cholesterol as a key parameter in improving pregnancy outcomes after assisted reproductive technology treatments in women with diabetes mellitus. To investigate the relationship between low-density lipoprotein cholesterol and pregnancy outcomes after assisted reproductive technology treatments in women with diabetes and infertility. 474 female patients diagnosed with diabetes were included in this study. The patients were divided into the high LDL-C group (≥3 mmol/L) and the low LDL-C group (<3 mmol/L). According to the protocol of ovarian stimulation, the clinical characteristics in ART cycles and pregnancy outcomes were compared separately. The data were analyzed after propensity score matching. In the GnRH antagonist protocol group, there were no significant differences in baseline characteristics between the high- and low-LDL-C groups. Nevertheless, ART treatment characteristics and pregnancy outcomes did not differ significantly between the 2 groups (P>.05). However, the rate of early miscarriage in GnRH antagonist protocol-FET cycles had a significantly positive association with LDL-C level (P=.0004).In the long-acting GnRH agonist protocol group, there were no significant differences in baseline characteristics between the high- and low-LDL-C groups; however, total cholesterol, triglycerides, and AST/ALT levels were significantly higher in the high-LDL-C group (P<.05). Although the clinical pregnancy rate of fresh embryo cycles in the high-LDL-C group was considerably higher than that of the low-LDL-C group (P=.001), there was a statistical difference in the early miscarriage rate between the 2 groups. (P<.05). This study demonstrates that in infertile women with diabetes mellitus undergoing ART, elevated pretreatment LDL-C is a significant and modifiable marker associated with an increased risk of early miscarriage and a reduced live birth rate. The impact of LDL-C varies by ovarian stimulation protocol. These findings underscore the importance of integrating preconception lipid management into the clinical pathway and adopting a protocol-specific risk assessment to optimize pregnancy outcomes.