Relationship between triploidy and the numbers of oocytes, age and the pregnancy rate after intracytoplasmic sperm injection

Abstract

OBJECTIVE: To evaluate the effect of triploidy to the rates of clinical pregnancy, miscarriage rate and live-birth rate after intracytoplasmic sperm injection (ICSI) and the relationship between triploidy and age and the numbers of oocytes. DESIGN: Retrospective cohort study. MATERIALS AND METHODS: Patient(s): Four hundred and thirty-one patients undergoing their first IVF–embryo transfer cycle requiring ICSI among all 1682 IVF cycles between July 1, 2001 and December 31, 2007 in the reproductive medical center were collected for study. Main Outcome Measure(s): GnRH agonist was used for pituitary suppression in the luteal phase. Split doses of recombinant FSH or purified hMG were used to induce multiple follicle development. Patients were divided into two groups on the basis of the proportion of triploid after ICSI that was observed at the time of fertilization assessment: group 1(n1=403) included patients with ≤20% (0%∼20%) three-pronuclear (3PN) zygotes, and group 2(n2=28) included patients with >20% 3PN zygotes. The proportion of triploid, the age, numbers of oocytes, pregnancy rates, miscarriage rates and live-birth rates in group1 were compared with that of group2. Differences in proportions were analyzed with Chi2 or Fisher's exact test. Continuous variables were assessed by t test. RESULTS: The mean (±SD) age of group1 (≤20% triploid fertilization) (32.0 ± 4.56y) was similar to group2 (>20% triploid fertilization) (32.46 ± 4.75y; P>0.05). No significant difference was noted between groups with the other parameters, such as baseline FSH, E2 levels in the day of HCG administered, number of embryos transferred. The mean number of oocytes obtained was no difference between group 1 and group 2 (12.33±7.36 vs. 10.33±5.57; P>0.05). The pregnancy rate, miscarriage rate and live-birth rate were no difference in group1 and group2 (150/253 vs. 9/19, P>0.05; 37/150 vs. 3/9, P>0.05; 113/150 vs 6/9, P>0.05). CONCLUSIONS: The proportion of triploid zygotes after ICSI had no effect on the rates of clinical pregnancy, quality of embryos and live-birth rates. We can not predict the outcomes of IVF cycle after ICSI by triploidy proportion.