Objective: To study the factors affecting the incidence of polyploidy in an assisted reproduction program.
Design: Retrospective analysis.
Setting: University-based subfertility clinic.
Patients and methods: Subfertile patients were treated in 163 treatment cycles of in vitro fertilization (IVF) or pronuclear stage tubal transfer (PROST). The relationship between the incidence of polyspermy and the indication of subfertility, the stimulation protocol, the oocyte, and the semen parameters were analyzed.
Results: Eighty-nine of the 1,149 oocytes were polyploid (7.8%). The incidence of polyploidy was not affected by the indication for IVF, the age of the patients, the stimulation protocol, the maturity of oocytes as assessed by the appearance of the cumulus, the sperm concentration, the number of sperm inseminated, the serum estradiol level, and the number of oocytes retrieved. The incidence was increased when: (1) the serum estradiol fell before the administration of human chorionic gonadotrophin; (2) the oocyte retrieval-insemination interval was 6 hours or more; (3) the sperm motility was 70% or more; (4) the percentage of sperm with normal morphology was 50% or more.
Conclusion: The incidence of polyploidy was affected by the serum estradiol pattern, the preinsemination interval, sperm motility, and percentage of morphologically normal sperm.