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[Fertilization in vitro and microinsemination. 6 years of experience in the Ospedale Microcitemico of Cagliari].

BACKGROUND
In this study the results of six years experience (1993-1998) in IVF, ICSI and assisted hatching on 442 sterile couples for a total of 868 cycles are reported. Since 1997 ICSI has also been carried out in cases of azoospermia extracting mobile spermatozoa from the epididymal (MESA) or from the testicle (TESE).


METHODS
Ages ranged from 20 to 48 and mean years sterility was 5.868 cycles were carried out of which 153 (17.62%) were for IVF, 705 (81.22%) for ICSI and 10 (1.15%) for MESA and TESE. Assisted hatching was performed through "partial zona dissection" in 329 cases on a total of 987 embryos.


RESULTS
The pregnancy rates per embryo transfer in IVF and ICSI cycles were 22.4 and 19.96% respectively. Results considering patients age were: 33.87% below 35, 29.55% between 35 and 38 and 6.60% above 38. In the group of 189 assisted hatching patients the evolutive pregnancy rate rose from 15.78 to 26.40% and multiple pregnancies from 28.63 to 42%.


CONCLUSIONS
ICSI has offered high rates of fertilization and pregnancy even in extreme cases of oligoasthenospermia or cases of azoospermia adopting MESA or TESE techniques. A decisive factor on pregnancy rates is age, very low over 38 years. Assisted Hatching further increased the pregnancy rates.