| ART AND MICROSURGICAL TREATMENTS FOR INFERTILITY |
When sperm are unable to move through the genital tract due to uncorrectable blockage, sperm can be extracted directly from the epididymis via microsurgical techniques, such as microsurgical epididymal sperm aspiration (MESA). Congenital absence of the vas deferens or seminal vesicles or failed sterilization (vasectomy) reversal are additional reasons why MESA might be used.
Usually performed as an outpatient procedure, MESA can provide sperm for IVF cycles. Epididymal sperm are usually not fully motile, which means they cannot swim through the female reproductive tract to reach the egg. Therefore, epididymal sperm can be used in conjunction with IVF or ZIFT, which place the sperm in direct contact with the egg.
Another ART alternative for overcoming male infertility is micromanipulation. The success of IVF, GIFT and ZIFT has been limited when sperm quality is poor. Microsurgical intervention such as gamete micromanipulation may provide a hopeful solution. Your physician may suggest this procedure if the male partner has a very low sperm count, immotile (nonmoving) sperm or abnormally shaped sperm. Micromanipulation uses microscopic instruments to enhance the chances of fertilization of the egg or implantation of the embryo.
There are different approaches in micromanipulation:
Intracytoplasmic Sperm Injection (ICSI)
Pioneered in Belgiuim, ICSI is the newest micromanipulation procedure and is a promising new treatment for male infertility. This laboratory technique involves the injection of a single sperm into the egg, bypassing both the need to have the sperm swim through the reproductive tract to reach the egg and the need to have the sperm penetrate the egg. The female partner will undergo ovarian stimulation and egg recovery in preparation for micromanipulation and embro transfer.
ICSI may provide men who produce very low amounts of weak sperm a chance to establish a pregnancy. The sperm used for ICSI can be obtained by masturbation or directly from the testes.
If obtained from the testes, immature sperm are aspirated with a fine needle using the MESA technique. Although this sperm is not motile, it does have the right genetic material (nucleus with the right number of chromosomes). This procedure is used for men who have had vasectomies or who have neurological disorders and are unable to ejaculate. Once the sperm is obtained, it is injected directly into the egg.
The success rate of ICSI, probably the most effective of the new micromanipulation techniques, was initially placed at about 26% (pregnancies per cycle). Further experience has increased the success rate in some centers to as high as 35%.
Assisted Hatching
Assisted hatching is a form of embryo micromanipulation that involves the creation of an opening in the outer covering, or zona pellucida, of the embryo. This procedure helps a normal, growing embryo emerge from the covering and implant in the uterus, hopefully leading to pregnancy. This procedure is associated with an increased implantation rate, especially in older women.