Correlation of subendometrial-endometrial blood flow assessment by two-dimensional power Doppler with pregnancy outcome in frozen-thawed embryo transfer cycles

CONTEXT: Various markers have been proposed to evaluate endometrial receptivity, such as molecular markers and sonographic markers. Commonly used sonographic markers include endometrial thickness and pattern. A good endometrial blood flow is considered necessary for improved pregnancy outcome. AIM: The aim of the present study is to evaluate the role of subendometrial endometrial blood flow with two-dimensional-power Doppler (2D-PD) in predicting pregnancy outcome in hormone replacement frozen-thawed embryo transfer (FET) cycles. SETTING AND DESIGN: Prospective, non-randomized observational study. A total of 165 patients undergoing their first FET cycle were evaluated for subendometrial-endometrial blood flow by 2D-PD once the endometrium was ≥7 mm thick. Group A consisted of 127 women showing the presence of subendometrial-endometrial blood flow. Group B comprised of 38 women in whom subendometrial blood flow was absent. Progesterone supplement was added and transfer of 2-3 cleavage stage good quality embryos was done after 3 days. STATISTICAL ANALYSIS: Independent two-tailed t-test and Chi-square test. RESULTS: There was no significant difference in body mass index, endometrial thickness, follicle stimulating hormone, luteinizing hormone levels, number of mature oocytes, semen parameters and the number of good quality embryos in the two groups (P > 0.05). The mean age in Group A was 32.05 years and 33.73 years in Group B, and the difference was statistically significant (P = 0.04). Overall pregnancy rate (PR) was 30.90%. PRs were significantly higher in the presence of subendometrial-endometrial blood flow than in its absence (35.43% vs. 15.78%, P = 0.02). Furthermore, clinical pregnancy rate and implantation rate were significantly higher in Group A when compared to Group B (31.49% and 14.79% vs. 13.15% and 6.52%, P = 0.02 and 0.03, respectively). CONCLUSION: The presence of endometrial blood flow significantly improves cycle outcome in hormone replacement therapy-FET cycles.