14mm.Results Group thick cycles had significantly lower implantation and pregnancy rates compared with group normal cycles(9.1% versus 13.5% and 18.8% versus 27.0%,respectively).Group thick cycles had significantly higher miscarriage rates compared with group normal cycles(50.0% versus 19.0%,respectively).Conclusion Increased endometrial thickness is associated with the decreased implantation or pregnancy rates and the increased miscarriage rates in IVF-ET.