Mitochondrial DNA content reduction in the most fertile spermatozoa is accompanied by increased mitochondrial DNA rearrangement.

Study Question: Is there an association between male fertility and spermatozoa mitochondrial DNA (mtDNA) copy number and genome rearrangements?

Summary Answer: Normal spermatozoa not only have a lower mtDNA copy number but also more DNA rearrangements than spermatozoa of men with severe oligoasthenospermia (SOA).

What Is Known Already: While there is a consensus that mtDNA content is decreased in the most fertile spermatozoa, the role of mtDNA sequence alteration in male infertility is unclear. High-throughput sequencing, which allows an exhaustive analysis of mtDNA rearrangements and mutations, could be helpful in this context, but has yet to be used.

Change in the Strategy of Embryo Selection with Time-Lapse System Implementation-Impact on Clinical Pregnancy Rates.

Time-lapse systems (TLS) and associated algorithms are interesting tools to improve embryo selection. This study aimed to evaluate how TLS and KIDScore™ algorithm changed our practices of embryo selection, as compared to a conventional morphological evaluation, and improved clinical pregnancy rates (CPR). In the study group (year 2020, = 303 transfers), embryos were cultured in an EmbryoScope+ time-lapse incubator.

Impact of the type of endometrial oestrogen preparation for frozen-thawed embryo (vaginal or transdermal) on perinatal outcomes in an artificial cycle.

Introduction: Serum oestradiol concentration at the time of frozen embryo transfer (FET) in artificial cycle are lower when using transdermal administration of oestrogen for endometrial preparation compared to the vaginal route. This difference could have consequences for placentation and establishment of maternal-foetal circulation. The aim of our study was to compare the birth weight of newborns and the perinatal issues after FET in an artificial cycle with regard to the route of administration of oestrogens.

Endometriosis Lowers the Cumulative Live Birth Rates in IVF by Decreasing the Number of Embryos but Not Their Quality.

Endometriosis and infertility are closely linked, but the underlying mechanisms are still poorly understood. This study aimed to evaluate the impact of endometriosis on in vitro fertilization (IVF) parameters, especially on embryo quality and IVF outcomes. A total of 1124 cycles with intracytoplasmic sperm injection were retrospectively evaluated, including 155 cycles with endometriosis and 969 cycles without endometriosis.