Factors affecting pregnancy outcome in a gamete intrafallopian transfer (GIFT) programme.

OBJECTIVE To identify the factors that most significantly affected pregnancy rates in a gamete intrafallopian transfer (GIFT) programme. METHODS A total of 863 GIFT cycles were analysed retrospectively. The variables found to be associated significantly with pregnancy were then used to obtain multivariate analysis using logistical regression. RESULTS Overall and ongoing pregnancy rates were significantly better in patients < or = 38 years than in patients > 38 years (37.3% and 28.4% v. 23.7% and 11.0% respectively), and age was positively associated with success after GIFT (odds ratio (OR) 1.87, 95% confidence interval (CI): 1.22-2.85). Metaphase I (MI) oocytes were negatively associated with pregnancy (OR 1.54, 95% CI: 0.28-1.04). The highest pregnancy rates occurred when 3 metaphase II (MII) oocytes were transferred (39.8%, OR 7.51, 95% CI: 1.74-32.42). With regard to sperm morphology, overall pregnancy rates of 25.5% (< or = 4% normal forms) and 37.2% (> 4% normal forms) were obtained. Morphology of > 4% normal forms was positively associated with pregnancy (OR 1.58, 95% CI: 1.04-2.42). CONCLUSION The results of this study suggest that the most important factors influencing pregnancy rates in a GIFT programme are the woman's age and those factors pertaining to the characteristics of the gametes. Considering the emotional and financial costs it is important to relate this information to all prospective participants in a GIFT programme.