Pregnancy obtained with human testicular spermatozoa in an in vitro fertilization program

The fertilizing capacity of human testicular spermatozoa and the positive outcome of an in vitro fertilization program open a wide range of opportunities for men suffering from obstructive and inoperable azoospermia. In six cases, subzonal sperm injection or intracytoplasmic sperm injection techniques were applied to inject testicular spermatozoa into human oocytes. The fertilization rate after testicular sperm injection reached 45%. Normal cleavage was observed and replacement of 10 embryos in 6 patients resulted in one chemical and one ongoing pregnancy.

A monozygotic twin pregnancy after application of zona rubbing on a frozen-thawed blastocyst

Assisted hatching techniques enhance the success rate of implantation of in-vitro fertilized human embryos. We report here the successful transfer of a frozen-thawed human blastocyst on which we applied a non-invasive zona rubbing technique (reduction of the thickness of the zona pellucida by gentle rubbing with a microneedle). The implantation in the uterus led to the delivery of healthy monozygotic twins.

Techniques of sperm selection, improvement and separation in an in vitro fertilization program

The Authors present a review of the various techniques used for improving the fertility potential of sperm within the context of an in vitro fertilization (IVF) program. After a brief description of the mechanisms leading to normal in vivo fertilization, they discuss the different methods of selecting and improving sperm for IVF. They conclude that centrifugation on discontinuous Percoll gradients would seem to be the most efficient separation method from all points of view, while the addition of pharmacological agents to improve sperm quality and motility lead to extremely unsatisfactory results.