title: Implantation failures: success of assisted hatching with quarter-laser zona thinning.
abstract: Implantation failure after IVF is one of the factors associated with a reduced chance of pregnancy for some patients. Assisted hatching methodologies are designed to facilitate the embryo's escape from the zona pellucida, and this strategy has been suggested as a means of improving pregnancy rates in patients with previous implantation failure. The aim of this prospective and randomized study was to evaluate the efficacy of quarter-laser zona thinning assisted hatching (qLZT-AH) in improving the implantation of embryos in patients with previous implantation failure. A total of 150 patients with a history of previous implantation failure were treated with intracytoplasmic sperm injection, and allocated into two groups: group 1, only one previous implantation failure, and group 2, repeated implantation failures. The patients in each group were randomized at the time of embryo transfer into a control group (no qLZT-AH) or experimental group where qLZT-AH was performed. For patients with repeated implantation failures, the implantation rate in those who received laser-thinned embryos was significantly higher (P = 0.02) than in those whose embryos were not laser-thinned (10.9 and 2.6% respectively). However, this difference was not observed in patients who presented with only one previous implantation failure. The data demonstrate that qLZT-AH is an effective strategy for improving the implantation of embryos in patients with repeated implantation failures.
authors.affiliation: Centre for Human Reproduction Sinhá Junqueira-Ribeirão Preto, Rua D. Alberto Gonçalves, 1500-CEP 14085-100, Ribeirão Preto, SP-Brazil.
authors.forename: C G
authors.initials: CG
authors.lastname: Petersen
authors.forename: A L
authors.initials: AL
authors.lastname: Mauri
authors.forename: R L
authors.initials: RL
authors.lastname: Baruffi
authors.forename: J B A
authors.initials: JB
authors.lastname: Oliveira
authors.forename: F C
authors.initials: FC
authors.lastname: Massaro
authors.forename: K
authors.initials: K
authors.lastname: Elder
authors.forename: J G
authors.initials: JG
authors.lastname: Franco
mesh_terms: D000328:Adult; D010064:Embryo Implantation / Q000502:physiology*; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007246:Infertility / Q000628:therapy*; D053685:Laser Therapy; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic; D015044:Zona Pellucida / Q000528:radiation effects* / Q000648:ultrastructure