Preimplantation genetic testing for monogenic/single gene disorders in a family with Molybdenum co-factor deficiency / 中华医学遗传学杂志

OBJECTIVE@#To carry out preimplantation genetic testing for monogenic/single gene disorders (PGT-M) for a Chinese family affected with Molybdenum co-factor deficiency due to pathogenic variant of MOCS2 gene.@*METHODS@#A family with molybdenum co-factor deficiency who attended to the Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region in April 2020 was selected as the research subject. Trophoblast cells were biopsied from blastocysts fertilized by intracytoplasmic sperm injection. Embryos carrying the MOCS2 gene variant and chromosome copy number variation (CNV) of more than 4 Mb were detected by single-cell whole genome amplification, high-throughput sequencing and single nucleotide polymorphism typing. Embryos without or carrying the heterozygous variant and without abnormal chromosome CNV were transplanted. During mid-pregnancy, amniotic fluid sample was collected for prenatal diagnosis to verify the results of PGT-M.@*RESULTS@#Eleven oocytes were obtained, among which three blastocysts were formed through culturing. Results of genetic testing suggested that one embryo was heterozygous for the maternally derived MOCS2 gene variant and without chromosomal CNV. Following embryo transfer, intrauterine singleton pregnancy was attained. Prenatal diagnosis by amniocentesis at 18 weeks of gestation revealed that the MOCS2 gene variant and chromosomal analysis results were both consistent with that of PGT-M, and a healthy male infant was born at 37+5 weeks of gestation.@*CONCLUSION@#PGT-M has helped the couple carrying the MOCS2 gene variant to have a healthy offspring, and may become an important method for couples carrying other pathogenic genetic variants.

A point of confusion for embryologists in the identification of viable spermatozoa by the eosin-nigrosin test / 대한생식의학회지

A viable spermatozoon is a prerequisite for fertilization in intracytoplasmic sperm injection (ICSI). Thus, it is crucial to select viable but immotile spermatozoa on the day of ICSI. We report conflicting results in the identification of viable but immotile spermatozoa between the eosin-nigrosin staining and the laser test, which resulted in confusion for embryologists during assisted reproductive technology (ART). Three patients’ semen samples that showed no motile spermatozoa are described in this report. To identify viable spermatozoa, we used both the eosin-nigrosin test and the laser test for each sample, and repeated the semen analysis twice in each patient. Viable but immotile spermatozoa selected by the laser test were used for ICSI. Viable spermatozoa were detected by both the eosin-nigrosin and laser tests in two patients (case 1, 95.00% vs. 24.21% and 92.68% vs. 22.22%; case 2, 41.18% vs. 23.48% and 39.81% vs. 22.52%), indicating consistent results between the two methods. In the third patient, the eosin-nigrosin test yielded viability rates of 20.75% and 19.14%, while the result of the laser test was 0%. Thus, testicular aspiration was performed to collect viable sperm from this patient. Normal fertilization was achieved after the injection of viable but immotile spermatozoa selected from these patients by the laser test, resulting in the birth of two healthy babies. Our study documents a case where the eosin-nigrosin test showed a limitation in identifying viable but immotile spermatozoa for ART, while the laser test may overcome this limitation. Larger samples may be required to corroborate the clinical value of the laser test.

Influence of the insemination method on the outcomes of elective blastocyst culture / 대한생식의학회지

OBJECTIVE: The aim of this study was to explore the effects of the insemination method on the outcomes of elective blastocyst culture. METHODS: We retrospectively analyzed the outcomes of elective blastocyst culture performed between January 2011 and December 2014. RESULTS: There were 2,003 cycles of conventional in vitro fertilization (IVF) and 336 cycles of intracytoplasmic sperm injection (ICSI), including 25,652 and 4,164 embryos that underwent sequential blastocyst culture, respectively. No significant differences were found in the female patients' age, basal follicle-stimulating hormone level, basal luteinizing hormone level, body mass index, number of oocytes, maturity rate, fertilization rate, or good-quality embryo rate. However, the blastocyst formation rate and embryo utilization rate were significantly higher in the conventional IVF group than in the ICSI group (54.70% vs. 50.94% and 51.09% vs. 47.65%, respectively, p0.05). No cycles were canceled due to the formation of no usable blastocysts. CONCLUSION: Although the fertilization method had no effect on clinical outcomes, the blastocyst formation rate and embryo utilization rate in the ICSI group were significantly lower than those observed in the conventional IVF group. Therefore, more care should be taken when choosing to perform blastocyst culture in ICSI patients.

Effect of blastocyst quality on the strategy of single blastocyst transfer in frozen-thawed cycles / 中华妇产科杂志

Objective To investigate the effect of blastocyst quality on the strategy of single blastocyst transfer in frozen-thawed cycles. Methods A retrospective analysis was performed in Reproductive Medicine Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region on clinical data of single frozen-thawed blastocyst transfer cycles from January 2008 to December 2013. All cycles were divided into four groups (AA, AB/BA, BB, BC/CB) according to the blastocyst score, then the clinical outcomes were compared between groups. And on this basis, the clinical outcomes were further explored when the group of outcomes with single blastocyst transfer wasn′t ideal, which would diverted to transfer two blastocyst. Results In single frozen blastocyst transfer cycles, the clinical pregnancy rate of each group with the blastocyst scored AA, AB/BA, BB, BC/CB were 61.4%(470/765), 51.2%(330/645), 40.5%(407/1 005), 22.9%(60/262), live births rate in each group were 52.2%(399/765), 41.2%(266/645), 30.4%(306/1 005), 13.7%(36/262), and the abortion rate were 13.6%(64/470), 16.7%(55/330), 21.4%(87/407), 35.0%(21/60), separately. This showed that the clinical pregnancy rate and live births rate decreased significantly with the decline of blastocyst quality (P40%) and live births rate (>30%) could be obtained, however, the clinical pregnancy rate of 22.9% and live births rate of 13.7%could only be acquired when blastocyst scored BC/CB only transferred one embryo, which significant lower than those of each group scored ≥BB grade (P0.05). Conclusions Of single blastocyst transfer in frozen-thawed cycles, the clinical pregnancy rate and liver births rate showed significant upward trend, but the abortion rate showed significant downward trend, with the decline of blastocyst quality. When the blastocyst scored ≥BB grade, the single blastocyst transfer could be considered to be performed.