Abstract:

Objective To investigate the effects of artificial thinning by laser-assisted hatching (AH) on the clinical outcomes of frozenthawed embryo transfer on day 3. Methods One thousand and twenty-four cycles undergoing frozen-thawed embryo transfer on day 3 were selected. Nine hundred and sixty-four cycles underwent thawed embryo transfer on day 3 (non-AH group), and the other 60 cycles underwent transfer after artificial thinning by AH (AH group). The rates of implantation, clinical pregnancy, multiple pregnancy, live birth, abortion and biochemistry pregnancy were statistically analysed in two groups. Results The rates of implantation, clinical pregnancy, multiple pregnancy, live birth, abortion and biochemistry pregnancy in two groups were 43.2% and 24.2%, 58.3% and 43.2%, 45.7% and 26.9%, 78.4% and 77.7%, 21.6% and 22.3%, and 6.7% and 4.4% respectively. There were significant differences in the rates of implantation, clinical pregnancy and multiple pregnancy between two groups (P＜0.05). The rates of live birth, abortion and biochemistry pregnancy in AH group were higher than those in non-AH group, while there was no significant difference between two groups (P＞0.05). Conclusion Artificial thinning by AH can increase the rates of implantation and clinical pregnancy, while there is no significantly change in the rate of live birth.

Key words: laser, assisted hatching, frozen-thawed, transfer