Effect of maternal age on the pregnancy rate of patients with repeated implantation failure and recurrent miscarriage following PGS

Abstract

OBJECTIVE: To evaluate the clinical impact of PGD for aneuploidy screening on selected groups of patients in one center. DESIGN: Retrospective data analysis and clinical study. MATERIALS AND METHODS: Patient groups including RIF, Repeated Implantation Failure with ≥3 times of failed IVF; RM, Recurrent Miscarriage with ≥3 times of spontaneous miscarriages with or without IVF; AMA, Advanced Maternal Age ≥37 and ≤2 implantation failure or pregnancy loss; Others with higher aneuploidy risk undergoing PGS in our center after written consents. Single blastomere was biopsied from day 3 embryos and nucleus was fixed with Tween/HCL method. The FISH analysis was performed with eight chromosomes (13,15,16,18,21,22,X,Y). One of the inclusion criteria for this study was patients with a minimum of 7 biopsiable embryos. RESULTS: A total of 116 patients (149 cycles, average age 38) were recruited in this study including 51 patients (63 cycles, average age 37.5) with RIF, 29 patients (47 cycles, average age 38.4) with RM, 24 patients (27 cycles, average age 40.7) with AMA and 12 patients (12 cycles, average age 34.3) with others. Out of the 1568 biopsied embryos, 1452 had an intact nucleus, FISH results were obtained in 1405 embryos (97%). Thirty eight percent of the embryos were diagnosed as normal and a total of 409 embryos were transferred in 143 cycles (Ave. 2.86). The overall clinical pregnancy rate per cycle was 42%. The clinical pregnancy rate in each group was: RIF (33.3%), RM (34%), AMA (52%) and others (75%). Approximately fifty percent of those patients with RIF and RM were of advanced maternal age (≥37 yrs age). The clinical pregnancy rate of RIF patients older than 37 years was only 25%. A Similar pregnancy rate was observed (25%) for RM patients who were older than 37 years of age. The clinical pregnancy rate was higher in younger patient group with either RIF or RM (patients with age ≤36 was 52% and 47.4% respectively). The higher pregnancy rates in these younger patients (mainly in RM group) may be attributed to a higher percentage of normal embryos that were available for transfer (≤36 yrs vs ≥37 yrs age: RIF=42%, RM=47.5% vs RIF=35.8%, RM=36.7%; p<0.05 for RM group). CONCLUSIONS: The overall clinical pregnancy rate from this selected group of patients following aneuploidy screening was 42%. Our observational data indicates that aneuploidy screening has a positive impact in this selected group of patients. The maternal age was the main contributing factors in the pregnancy rate in RIF and RM patient groups.