Factors associated with the formation of triploid zygotes after intracytoplasmic sperm injection

Objective: To determine whether clinical or laboratory factors influence de velopment of triploid (3PN) zygotes after ICSI. Design: Retrospective review. Setting: The assisted reproductive technology program of Brigham and Women' s Hospital. Patient(s): Patients undergoing ICSI. Intervention(s): None. Main Outcome Measure(s): Cycles were divided into two groups: group A, cycl es with one or more 3PN zygotes after ICSI, and group B, cycles with no 3PN zygotes. Age, amount of gonadotropin administered, peak estradiol levels, number of follicles, number of oocytes retrieved and injected, time between retrieval and injection, oocyte abnormalities, sperm type and motile count , percentage of diploid zygotes, and ongoing pregnancy rates were compared between groups. Result(s): Compared with patients in group B, those in group A received few er ampoules of gonadotropins, had higher estradiol levels, and had more fol licles on the day of hCG administration, oocytes, immature oocytes and oocy tes injected and lower percentages of diploid zygotes. However, ongoing pre gnancy rates did not differ between groups. Conclusion(s): Patients who produce 3PN zygotes after ICSI are high respond ers to ovarian stimulation. The appearance of such embryos is not associate d with lower ongoing pregnancy rates and should not necessarily dictate alt erations in ovarian stimulation protocols. (C) 2000 by American Society for Reproductive Medicine.