Blastocyst euploidy and implantation rates in a young (<35 years) and old (≥35 years) presumed fertile and infertile patient population.

Objective: To examine the relationship between blastocyst euploidy and implantation rates in a presumed fertile patient population.

Design: Retrospective analysis.

Setting: Private IVF clinic.

Comparison of aneuploidy, pregnancy and live birth rates between day 5 and day 6 blastocysts.

Comprehensive chromosome screening is typically used for aneuploidy analysis of blastocysts. It is believed that either day of blastocyst development is acceptable. Euploidy rates and outcomes were examined between day 5 and day 6 blastocysts in two studies.

Outcomes of blastocysts biopsied and vitrified once versus those cryopreserved twice for euploid blastocyst transfer.

Trophectoderm biopsy with comprehensive chromosome screening (CCS) has been shown to increase implantation and pregnancy rates. Some patients desire CCS on previously cryopreserved blastocysts, resulting in blastocysts that are thawed/warmed, biopsied, vitrified and then warmed again. The effect of two cryopreservation procedures and two thawing/warming procedures on outcomes has not been effectively studied.

The origin, mechanisms, incidence and clinical consequences of chromosomal mosaicism in humans.

Background: Chromosomal mosaicism, the presence of two or more distinct cell lines, is prevalent throughout human pre- and post-implantation development and can lead to genetic abnormalities, miscarriages, stillbirths or live births. Due to the prevalence and significance of mosaicism in the human species, it is important to understand the origins, mechanisms and incidence of mosaicism throughout development.

Methods: Literature searches were conducted utilizing Pubmed, with emphasis on human pre- and post-implantation mosaicism.

Globozoospermia is mainly due to DPY19L2 deletion via non-allelic homologous recombination involving two recombination hotspots.

To date, mutations in two genes, SPATA16 and DPY19L2, have been identified as responsible for a severe teratozoospermia, namely globozoospermia. The two initial descriptions of the DPY19L2 deletion lead to a very different rate of occurrence of this mutation among globospermic patients. In order to better estimate the contribution of DPY19L2 in globozoospermia, we screened a larger cohort including 64 globozoospermic patients.