ABSTRACT
<p><b>OBJECTIVE</b>To study the relationship between the percentage of polypronuclear zygotes and clinical pregnancy following IVF.</p><p><b>METHODS</b>We collected the data of 954 IVF cycles, and according the percentage of polypronuclear zygotes in the IVF cycles, allocated them to Groups A (without polypronuclear zygotes) , B (with < 30% polypronuclear zygotes) and C (with > or = 30% polypronuclear zygotes). Then we analyzed the relationship between the percentage of polypronuclear zygotes and the rate of clinical pregnancy.</p><p><b>RESULTS</b>Compared with Group A, Group C showed a significantly lower rate of clinical pregnancy (43.2% vs 28. 1%, P < 0.05), while Group B exhibited a markedly higher rate (43.2% vs 52.36%, P < 0.05) and obviously decreased polypronuclear zygote formation with the increase of age (35.6% vs 24.1%, P < 0.05).</p><p><b>CONCLUSION</b>The percentage of polypronuclear zygotes in IVF cycles may serve as a prognostic indicator of the clinical outcome.</p>