الفهرس 
MethodologyOnly 14 pages are availabe for public view
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Abstract
Sperm retrieval techniques are based on acquiring sperm from the reproductive tract, including three sources which are the vas deferens, epididymis, and testicle. They are indicated for men in whom the transport of sperm is not possible because the ductal system that normally carries sperm to the ejaculate is either absent or unreconstructable, or if sperm production is low, as in some cases of non obstructive azoospermia. The first and most common indication is congenital bilateral absence of the vas deferens (CBAVD) which is the most common cause of obstructive azoospermia in men with primary infertility. Surgical sperm retrieval methods have been proposed as a means of obtaining spermatozoa for assisted reproduction in men with anejaculation, i.e. the absence of antegrade or retrograde ejaculation. However, surgical methods are only to be considered when penile vibrostimulation (PVS) or electroejaculation (EEJ) has failed. Among the three sources of retrieved sperm, vasal sperm is the most “mature” or fertilizable sperm, as this sperm has already passed through the epididymis, where sperm maturation occurs. Epididymal sperm aspiration is performed when the vas is either absent such as with CBAVD or is scarred from prior surgery, trauma, or infection. It is also performed in cases of anejaculation due to diabetes or spinal cord injury. The newest of the three sperm aspiration techniques, testicular sperm retrieval, was first reported in 1993, one year after ICSI. Testicular spermatozoa can be retrieved in some patients with non obstructive azoospermia (NOA) because of persistence of isolated foci of active spermatogenesis. In patients with OA, MESA or PESA yielded approximately 100 percent success rate for sperm retrieval. If spermatozoa are not found in the epididymal aspirate, fine needle TESA will result in retrieval of testicular sperm in virtually all cases of OA. However, in patients with NOA, epididymal aspiration is useless and the patients should be offered surgical retrieval of testicular sperm, preferably performing an open biopsy. As PESA has definitive clinical advantages compared with the open surgery required in MESA, it may be offered as the treatment of choice for patients with obstructive azoospermia. The sperm retrieval rate with microdissection TESE is higher than with an open biopsy, in which even multiple samples are obtained (conventional TESE). In some centers, microdissection TESE has become a standard treatment for patients with NOA. The factors that consistently results in poorer ICSI outcomes is advanced maternal age; quality of embryos is a significant predictor of fertilization rates, and number of embryo transferred impacts implantation and pregnancy rates, ovarian reserve. Studies are inconclusive regarding whether procedural or paternal factors negatively affect ICSI outcomes. Conventional sperm parameters and paternal age do not appear to influence ICSI outcomes, although sperm origin (i.e. ejaculated versus surgically retrieved) may have an effect on fertilization, implantation, and pregnancy rates. Also the strongest indicator for finding sperm for ICSI was testicular histopathology, which was significantly higher in cases with sever hypospermatogenesis, in agreement with some reports in the literature. PGD technique is a postfertilization, but pretransfer, method that involves testing embryos created by IVF. It was first performed in 1990 for patient with known familial hereditary diseases. PGD is typically performed 3 days after egg retrieval when the embryo has reached 6 to 8 blastomere stage. PGD should be offered for 3 major groups of disease, (1) sex-linked disorders, (2) single gene defects, and (3) chromosomal disorders.