Assessment of endometrial and subendometrial blood flow in women undergoing frozen embryo transfer cycles

Abstract

This study evaluated whether 3D power Doppler (3DPD) indices from endometrium and subendometrium can identify increases in endometrial volume/vascularity induced by exogenous oestradiol and subsequent introduction of progestogens in women undergoing frozen–thawed embryo transfer (FET). Oral oestradiol was administered at increasing doses after down-regulation to prepare the endometrium and progestogens were used for luteal support. 3DPD data sets were acquired at down-regulation, on days 5, 10 and 15 of oestradiol administration and at the time of FET. Endometrial thickness was measured using the multiplanar method and endometrial volume and blood flow from the endometrium and subendometrium were estimated using virtual organ computer-aided analysis and shell-imaging. This study evaluated 45 women at least once: 19 achieved clinical pregnancy (CP); 21 were evaluated at down-regulation (eight CP), 26 at day 5 (10 CP), 31 at day 10 (12 CP), 31 at day 15 (13 CP) and 16 at FET (seven CP). Changes were observed in all parameters between the examinations; however, differences between women who achieved CP and those who did not were not significant. 3DPD angiography is not a sufficiently sensitive tool to predict the outcome of FET.We evaluate whether 3D ultrasound using power Doppler (3DPD) indices from endometrium and subendometrium can identify predictable increases in endometrial volume and vascularity induced by serial increments in exogenous oestradiol and the subsequent introduction of progestogens in women undergoing frozen–thawed embryo transfer (FET) using hormone replacement therapy to prepare the endometrium. Oral oestradiol was administered at increasing doses after down-regulation to prepare the endometrium and progestogens were used for luteal support. 3DPD data sets of the uterus were acquired at down-regulation, on days 5, 10, and 15 of oestradiol administration, and at the time of FET. Endometrial thickness was measured. Endometrial volume and blood flow from the endometrium and subendometrium were measured using virtual organ computer-aided analysis (VOCAL) and shell imaging. This study evaluated 45 women at least once: 19 achieved clinical pregnancy (CP); 21 were evaluated at down-regulation (eight CP), 26 at day 5 (10 CP), 31 at day 10 (12 CP), 31 at day 15 (13 CP) and 16 at FET (seven CP). Changes were observed in all the parameters between the examinations; however, differences between women who achieved CP and those who did not were not significant, suggesting that quantitative 3D power Doppler angiography is not a sufficiently sensitive tool to predict the outcome of FET treatment.