Thursday, October 16, 2008

Intracytoplasmic Sperm Injection ( ICSI )


Although cases presenting with mild sperm abnormalities can be successfully treated by "classical" IVF, today intracytoplasmic sperm injection ( ICSI ) offers a new dimension of therapy for all the moderate and more severe forms of male infertility.

Indications for ICSI include:

Men presenting with low sperm concentration, motility and / or morphology (irrespective of the degree of these abnormalities), antisperm antibodies, or with poor scores in the functional bioassays

Cases of partial or total fertilization failure in a previous IVF attempt ( with overt or more subtle sperm deficiencies or even with normal semen analysis )

Men presenting with absence of sperm in the ejaculate ( azoospermia ).

These cases were typically considered irreversible with donor sperm or adoption being considered as the only viable options. These challenging cases include two main types of problems:
-obstructive lesions of the male genital tract ( such as congenital bilateral absence of the vas deferens, inflammatory occlusions, previous vasectomy, and others )
-patients presenting with different degrees of testicular insufficiency ( hypospermatogenesis or poor sperm production of testicular origin ).
The former cases can be successfully treated by new techniques of sperm aspiration from the epididymis or the vas deferens followed by ICSI. In the latter cases, sperm can be obtained from the testes by performing an open testicular biopsy or by needle aspiration, also followed by ICSI.

In all these cases, the possibility of freezing "extra" sperm obtained at the time of the urological intervention ( prior to or at the time of IVF / ICSI ) should always be considered. Frozen - thawed sperm may maintain viability and therefore can be used in future ICSI cycles. Sperm freezing is a mandatory and efficient means of maintaining the reproductive potential of men who will have radical therapies in cases of curable cancer. Our sperm bank is ISO 9001:2000 certified and serves local, out - of - state, and international physicians and patients.

Because of the high incidence of male infertility and the outstanding success of the technique, currently we perform ICSI in 40% of all IVF cases. For this technique, success has to be assessed both in terms of fertilization and pregnancy outcome.

There are probably several thousand babies born worldwide through ICSI. Worldwide registries note that in 97% or more of the times that ICSI results in delivery of normal healthy babies. These numbers are probably very close to the results achieved in standard IVF therapy and probably not far from natural reproduction.

However, we are learning more and more about incidences of chromosomal / genetic problems in the infertile man. New techniques are being developed; statistics quote approximately 10% incidence of genetic or chromosomal abnormalities in men with either severely low sperm counts ( oligospermia ) or lack of sperm in the semen ( azoospermia ). For this reason, and in addition to performing a chromosomal evaluation of the fetus ( baby in the uterus ) in early pregnancy either by chorionic villus sampling or amniocentesis, the Jones Institute recommends a genetic consultation.

Intracytoplasmic sperm injection ( ICSI ) research has focused on the impact of ICSI on the meiotic spindle. The spindle is a "web like" intracellular structure that is crucial for normal chromosome alignment and separation during fertilization. We now use a highly specialized imaging system for ICSI procedures, which allows us to visualize and avoid damaging the meiotic spindle. Extensive research indicates that overall there is no increase in the rate of birth defects or other abnormalities after the ICSI procedure.

However, there is some concern that ICSI could increase the incidence of male infertility in offspring and that it could enhance the occurrence of rare sexual chromosomal abnormalities. In nature, the most viable sperm reaches and fertilizes the egg; however, in ICSI, sperm are manually selected thus bypassing this natural selection process. Clinical data are not yet available to conclusively rule out this possibility. We recommend that men with severe oligospermia or non - obstructive azoospermic undergo a baryotype ( blood chromosomal analysis ) and an examination of presence / absence of microdeletions of a Y - chromosome. Genetic counseling is offered as appropriate.

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