Two years of assisted fertilization by partial zona dissection in male factor infertility patients.
OBJECTIVE
To assess partial zona dissection in our routine IVF-ET program over a 2-year period.


METHODS
Partial zona dissection before insemination on the day of oocyte collection or 24 hours after unsuccessful conventional IVF. In a subgroup of patients, oocytes were randomized to either partial zona dissection before insemination or IVF.


METHODS
University infertility clinic.


METHODS
Couples who suffered principally from male factor infertility or who had failed fertilization previously.


METHODS
Micromanipulation of oocytes with partial zona dissection.


METHODS
Comparison of fertilization rate, embryo morphology, and implantation rate between partial zona dissection inseminated oocytes and conventional IVF inseminated oocytes (controls).


RESULTS
Five pregnancies were established in 199 patients. The incidence of polyspermy was significantly higher in the partial zona dissection group than in conventional IVF (4.8% versus 1.3%). There were no significant differences in the remaining parameters. The fertilization rate of partial zona dissection and reinsemination was significantly higher than conventional IVF insemination (13.6% versus 4.5%) but similar to the rate obtained when partial zona dissection was applied before insemination (13.6% versus 15.7%).


CONCLUSIONS
Oocytes treated by partial zona dissection did not exhibit a greater fertilization rate than conventional IVF inseminated oocytes. Partial zona dissection may not be a useful technique for treating severe male factor infertility.
Department of Obstetrics and Gynecology, Institut Universitari Dexeus, Barcelona, Spain.
G
G
Calderón
A
A
Veiga
J
J
Penella
P N
PN
Barri
D000328:Adult; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007248:Infertility, Male; D008297:Male; D008866:Microsurgery; D011897:Random Allocation; D013084:Sperm-Ovum Interactions; D015044:Zona Pellucida