Ultrastructural analysis of TESE and semen sperm tails from patients exhibiting absolute immotility on the day of ICSI

Differential transcriptomic profile in spermatozoa achieving pregnancy or not via ICSI

Basic sperm analysis is limited as a method of estimating pregnancy. This study’s objective was use of microarray technology to differentiate the gene expressions of spermatozoa that achieved pregnancy in an intracytoplasmic sperm injection (ICSI)cycle in an oocyte donation programme with those that did not achieve pregnancy. A study of nested cases and controls was designed to evaluate fresh and frozen spermatozoa from infertile males undergoing ICSI with donor oocytes. The global genome expression of pooled samples from each group (achieving pregnancy versus those that didn’t, from fresh or frozen spermatozoa)was compared using microarray analysis. The level of expression of some of the transcripts from fresh spermatozoa was shown to differ for those that achieved pregnancy versus those that didn’t. Additionally, exclusively expressed transcripts were identified for both outcome groups. Analysis of frozen spermatozoa didn’t reveal differential expression, but exclusively expressed transcripts were detected. Lists of the transcripts were systematically analysed using different databases in order to provide information about them and their relationship with male fertility. The results revealed profound differences between the expression profiles of spermatozoa that resulted in pregnancy versus those that didn’t. These differences may explain ICSI failure associated with male factor infertility.

Outcome of ICSI with ejaculated spermatozoa in a series of men with distinct ultrastructural flagellar abnormalities

BACKGROUND

Severe sperm motility impairment results in human infertility, which can be overcome by ICSI. Whether some particular, possibly genetic, flagellar abnormalities can influence embryonic development is a matter of debate.

METHODS

Analysis of ultrastructural flagellar abnormalities and ICSI outcomes with ejaculated spermatozoa in a series of 21 infertile patients with asthenozoospermic or dyskinetic spermatozoa due to a primary and specific flagellar abnormality was carried out.

RESULTS

Patients were sorted into six categories according to flagellar ultrastructural defects. Oocyte fertilization occurred in the 21 couples with a mean 2PN fertilization rate reaching 61.85%. No difference was observed in the kinetics of in vitro development or in the morphological quality of the embryos between the different types of flagellar abnormalities. Pregnancy occurred in 12 couples (57.1%) and delivery in nine couples (42.86%). Both the implantation rate and the clinical pregnancy rate per cycle were lower in type III abnormalities and in patients with an initial sperm motility less than 5%.

CONCLUSIONS

The rate of ICSI success may be influenced by the type of flagellar abnormality. ICSI provides a suitable solution for patients with sperm flagellar defects but raises the question of the consequences of a specific (and primary flagellar) abnormality on oocyte fertilization, on embryo and fetal development as well as on live birth.