Objective: To determine the impact of endometrial thickness and texture on clinical pregnancy, implantation and miscarriage rates in intracytoplasmic sperm injection (ICSI) and embryo transfer cycles.
Study design: A total of 758 consecutive infertile women (n = 1,087 cycles) undergoing ICSI and embryo transfer (ET) because of severe male factor infertility were retrospectively enrolled in Hacettepe University, Faculty of Medicine. Three groups of patients undergoing ICSI were identified based on endometrial thickness on the day of human chorionic gonadotropin (hCG) administration: < 7 mm (group A: 26 patients, 42 cycles), 7-14 mm (group B: 663 patients, 956 cycles) and > 14 mm (group C: 69 patients, 89 cycles).
Results: Although there was a trend of lower clinical pregnancy rate per embryo transfer in group A (35.0%) compared with group B (43.1%), it did not reach statistical significance; however, it was significantly higher in group C (59.1%), (p < 0.05). The respective figures for implantation rates were 37.6%, 10.4%, and 23.0% (p < 0.01).
Conclusion: Endometrial thickness < 7 mm on the day of hCG is associated with lower pregnancy rate when compared with 7-14 mm and > 14 mm; however, a clinical pregnancy rate of approximately 35% still warrants not abandoning fresh embryo transfer in such cases.