Neonatal outcomes of live births after blastocyst biopsy in preimplantation genetic testing cycles: a follow-up of 1,721 children.

OBJECTIVE: To investigate whether blastocyst biopsy in preimplantation genetic testing (PGT) increases the risk of adverse neonatal outcomes. DESIGN: Retrospective cohort study. SETTING: University-affiliated center. PATIENTS: Live births after blastocyst biopsy combined with frozen ET (PGT group) and frozen blastocyst transfer after in vitro fertilization or intracytoplasmic sperm injection (control group). INTERVENTION(S): Blastocyst biopsy. MAIN OUTCOME MEASURE(S): Gestational age (GA), birth weight (BW), and rates of preterm birth (PB), very preterm birth (VPB), extreme preterm birth (EPB), low birth weight (LBW), very low birth weight (VLBW), and macrosomia. RESULT(S): No significant differences were observed in the sex ratio, GA, PB, VPB, EPB, BW, or rates of LBW, VLBW, and macrosomia between the PGT and control groups for either singletons or twins. However, the cesarean section rate of the PGT group was significantly higher than that of the control group for twins (adjusted odds ratio, 2.383 [1.079, 5.259]). Regarding fluorescence in situ hybridization-PGT neonates, neonatal outcomes, including GA, BW, and rates of PB, VPB, LBW, and VLBW, did not differ between the different groups of biopsied cells (≥10 group and <10 group) for either the grade B or grade C trophectoderm score subgroups; however, in the grade B trophectoderm score subgroup, the rate of boy babies in the ≥10 group was significantly higher than that in the <10 group (83.3% vs. 40.9%). The association between the number of biopsied cells and GA/BW was not statistically significant. CONCLUSION(S): Blastocyst biopsy may not add additional risk to neonatal outcomes when compared with a control group.

Analysis of the first mitotic spindles in human in vitro fertilized tripronuclear zygotes after pronuclear removal.

Tripronuclear zygotes (3PN) occur in about 5% of cases in human IVF programmes. Human 3PN zygotes derived from a conventional IVF programme may contain not only the extra male pronucleus but also a supplementary centriole. Researchers have tried to restore diploidy by removing the extra male pronucleus of the tripronuclear zygote. However, it is still unknown whether the procedure can remove the supernumerary centriole. The objective of this study was to evaluate the safety of this manipulation by analysing the first mitotic spindles of 3PN zygotes that have undergone extra pronuclear removal. A controlled trial was conducted using human 3PN zygotes from conventional IVF treatment. In the experimental group, the assumed extra male pronuclei in the 3PN zygotes were removed. The first cleavage patterns and in vitro development were observed in both groups; polarized light microscopy and immunocytochemistry were used to analyse the first mitotic spindles. The blastocyst formation rate was significantly higher (P = 0.007) in the pronuclear-removed group (16.0%) than in the control group (4.5%). No significant differences were found between the groups in the first cleavage patterns and the distributions of the first mitotic spindle structure. This study suggests that, after extra pronuclei are removed, the developmental potential of human 3PN zygotes is improved. However, the abnormal patterns in the first mitosis are not corrected by this removal.

[Diagnosing achondroplasia by single cell nested-PCR].

OBJECTIVE: To research on the reliability of diagnosing achondroplasia (ACH) on single cell level and to provide a basis for preimplantation genetic diagnosis(PGD). METHODS: The high-frequency mutation region G380R of fibroblast growth factor receptor 3(FGFR3) gene was amplified by nested-PCR with single lymphocyte and single blastomere. The products of PCR were digested by restriction enzyme Bfm I, then the digested products were detected by 10% polyacrylamida gel electrophoresis(PAGE). RESULTS: The amplification success rate, allele dropout rate and correct diagnosis rate of single lymphocyte's PCR were 90.4%, 8.2% and 91.8%,respectively. The amplification success rate of single blastomere was 75.4%. CONCLUSION: The diagnosis of ACH by single cell nested-PCR is comparatively stable and reliable.