RÉSUMÉ
Objective To explore the efficacy of long- and short-acting triptorelin on pituitary down-regulation in long protocol and the pregnancy outcome in vitro fertilization and embryo transfer (IVF-ET) . Methods Three hundred and seventeen patients for IVF-ET were enrolled as study and randomized them into two groups. In group A (n=145), patients received single dose subcutaneous injection of 1.25 mg long-acting diphereline in mid-luteal phase. In group B (n=172), patients received 0.1 mg/d subcutaneous injection of short-acting diphereline in mid-luteal phase for 14-18 days until pituitary suppression were got,and then reduced to 0.05 mg/d until the injection of HCG. Results The dose and the days of gonadotropin administration in group A were bigger and longer than those in group B ( 0.05) . But clinical pregnancy rate of group B had increasing trend. Conclusion Administration of short-acting diphereline has the similar effect with that of long-acting diphereline on pituitary down-regulation in long protocol. Short-acting diphereline requires lower amount of gonadotropin and is more flexible,so it should be recommended.