RESUMO
BACKGROUND: Poor implantation rates continue to be the determinant factor for results in assisted reproductive techniques; many factors are thought to be involved including embryo quality, endometrial receptivity and embryo transfer. Assisted hatching has been proposed as a technique to improve implantation rates in selected groups of patients, especially with poor prognosis. OBJECTIVE: To evaluate the impact of the laser assisted hatching performed with quarter technique in patients with poor prognosis. MATERIAL AND METHODS: Prospective, controlled and randomized clinical study. The study group included patients with poor prognosis: maternal age ≥ 38 years, basal FSH ≥ 12.0 mUl/mL, two or more previous FIV/ ICSI failures. The control group don't received neither assisted reproductive techniques. RESULTS: We registered 303 cycles: n=1 54 in study group (laser assisted hatching) and n = 149 in control group. Clinical pregnancy (40.1 vs 19.7%) and implantation (17.5 vs 8.3%) rates were significant higher in laser assisted hatching group, there were not significant differences between multiple pregnancy (13.11 vs 10%) and miscarriage (14.7 vs 17.2) rates. CONCLUSION: Laser assisted hatching with quarter technique improves pregnancy and implantation rates in poor prognosis patients.