Assisted hatching using a 1.48‐µm diode laser: Evaluation of zona opening and zona thinning techniques in human embryos

Abstract

We assessed the effectiveness of assisted hatching using a 1.48-µm diode laser in human embryos, comparing zona opening and zona thinning techniques. A total of 56 day 3 embryos were assigned randomly to a zona opening group, a zona thinning group, or a control group. We then carried out assisted hatching using the OCTAX Laser Shot system (MTG Medical Technology, Altdorf, Germany) in the first two groups. In the zona opening group, the inner membrane of the zona pellucida was broken to create a full-thickness opening. In the zona thinning group, the inner membrane of the zona pellucida was not breached. After the laser procedure, embryos were cultured to the hatched blastocyst stage. Blastocyst development rates did not differ significantly between the three groups. In the zona opening group, blastocysts were significantly more likely to hatch than those in the control group ( ≤ 0.05) and no arrested hatching of blastocysts was observed. Assisted hatching using a 1.48-µm diode laser in the zona opening technique increases the likelihood of blastocyst hatching in human embryos and does not adversely effect subsequent embryo development. (Reprod Med Biol 2006;: 221-226).

An investigation of the effects of laser-assisted zona pellucida drilling on the preimplantation mouse embryo and the competency of embryo implantation

“…In line with previous findings involving mouse embryos and human embryos, we found that all three ZP manipulations significantly advanced the initiation of embryo hatching at E4.5, with a highest proportion of embryos hatching found in the ZP drilling group (14,17,18,20,21,(49)(50)(51). In addition, the reduced number of cells in hatching embryos from the ZP drilling group supported the fact that the artificially induced ZP opening allows embryos to begin hatching without reaching a certain embryonic cell number; this observation concurred with previous studies (20,31).…”

Laser-assisted hatching in lower grade cleavage stage embryos improves blastocyst formation: results from a retrospective study

“…The other studies, however, concluded that LAH on multiple-cell stage embryos failed to improve blastocyst formation and clinical pregnancy rate [25,26]. Wong et al reported that 114 donated blastomere stage embryos were divided into three groups: complete LAH, partial LAH and N-LAH.…”

Cryoprotective effects of various saccharides on cryopreserved mouse sperm from various strains

“…29 Nakagata et al, 30 Kawase et al 31 and Kaneko et al 32 reported that the problem of low fertility of C57BL/6 sperm caused by freezing damage is overcome by partially dissecting the zona pellucida, which also improves the fertility of sperm from subfertile transgenic mice, 33 and helps human IVF embryos at the blastocyst stage to hatch effectively. 34 In conclusion, we have shown that to preserve the fertility of mouse sperm from some inbred and hybrid mice at a high level, maltose, melezitose and raffinose are the best protectants to use in cryopreservation.…”

“…and Kaneko et al 32 . reported that the problem of low fertility of C57BL/6 sperm caused by freezing damage is overcome by partially dissecting the zona pellucida, which also improves the fertility of sperm from subfertile transgenic mice, 33 and helps human IVF embryos at the blastocyst stage to hatch effectively 34 …”