Quantitative three-dimensional sonographic assessment of pelvic blood after transvaginal ultrasound-guided oocyte aspiration: factors predicting risk.

Objectives: To evaluate the fluid volume in the pelvis immediately and 3-5 days after transvaginal ultrasound-guided oocyte aspiration (TOAS) and to identify predictive factors for intraperitoneal bleeding.

Methods: This was a prospective study of 83 infertile women undergoing controlled ovarian hyperstimulation followed by TOAS and embryo transfer (ET). Pelvic blood volume was measured by three-dimensional (3D) ultrasound examination 3-5 h after TOAS (post-TOAS), and prior to ET (2-3 days after TOAS; pre-ET). Pelvic blood volume was then correlated with the following procedure-related variables: day of hCG administration: number and diameter of ovarian follicles, endometrial thickness, serum estradiol levels; day of TOAS: number of retrieved oocytes, patient's perceived pain (Likert scale), duration of TOAS, diameters (using two-dimensional (2D) ultrasound) and 3D volume of pelvic fluid; day of ET: 2D diameters and 3D volume of pelvic fluid, perceived pain; pregnancy rate.

Results: The mean +/- SD volume of blood measured by 3D ultrasound after TOAS and before ET was 12.94 +/- 16.88 (range, 0-98.00) mL and 19.13 +/- 17.84 (range, 0-70.20) mL, respectively. Blood volume in the pelvis correlated most strongly with number of oocytes retrieved (post-TOAS: P < 0.01; pre-ET: P < 0.05), followed by pain level (post-TOAS: P < 0.01), number of follicles (post-TOAS: P < 0.05) and endometrial thickness (post-TOAS: P < 0.05). When all study variables were held constant, the number of oocytes and serum estradiol level proved to be significant predictors of the amount of fluid in the pelvis (post-TOAS/pre-ET: P < 0.01). If 2D ultrasound was used, the best predictor of fluid volume after TOAS was the width of the fluid scanned in the pelvis (P < 0.001).

Conclusions: The amount of blood in the pelvis following TOAS in the present series was within acceptable clinical limits. The number of retrieved oocytes and pain after TOAS were found to be indicators of patients at risk of excessive bleeding. These findings have important implications for the improvement of postprocedural care.