PURPOSE: To elucidate the appropriateness of current indications for assisted hatching (AH) in cleavage stage human embryos and to confirm our preliminary findings that only young patients (about 67%) benefit from AH. METHODS: Prior to transfer, 2 of 3 embryos selected for ET were subjected to laser assisted hatching (LAH). Control group consisted of patients matched by similar characteristics and protocol except LAH was not performed. RESULTS: The clinical pregnancy rate in women < or = 36 years was 64.9% (24/37) for embryos subjected to LAH but was significantly lower (p = 0.029) in the control (33.3%; 10/30). The implantation rate in women < or = 36 years in the test group was 38.1% (40/105) that was significantly higher than that of the control group (17.5%, 14/80; p = 0.0039). CONCLUSIONS: LAH is beneficial for women < or = 36 years but not for women > or = 37 years, for embryos with thin zonae (< or = 16 micron) but not with thick zonae (> or = 17 micron), and for those with repeated failures (37-50%).
PURPOSE: To elucidate the appropriateness of current indications for assisted hatching (AH) in cleavage stage human embryos and to confirm our preliminary findings that only young patients (about 67%) benefit from AH. METHODS: Prior to transfer, 2 of 3 embryos selected for ET were subjected to laser assisted hatching (LAH). Control group consisted of patients matched by similar characteristics and protocol except LAH was not performed. RESULTS: The clinical pregnancy rate in women < or = 36 years was 64.9% (24/37) for embryos subjected to LAH but was significantly lower (p = 0.029) in the control (33.3%; 10/30). The implantation rate in women < or = 36 years in the test group was 38.1% (40/105) that was significantly higher than that of the control group (17.5%, 14/80; p = 0.0039). CONCLUSIONS: LAH is beneficial for women < or = 36 years but not for women > or = 37 years, for embryos with thin zonae (< or = 16 micron) but not with thick zonae (> or = 17 micron), and for those with repeated failures (37-50%).
Authors: R G Edwards; S B Fishel; J Cohen; C B Fehilly; J M Purdy; J M Slater; P C Steptoe; J M Webster Journal: J In Vitro Fert Embryo Transf Date: 1984-03