Abstract
Recent advances in three-dimensional ultrasound (3-D US) have made accurate non-invasive measurements of the follicular, ovarian, and endometrial volumes feasible. Storage capacities, reconstruction of the volume images, and simultaneous viewing of all three orthogonal planes are main advantages of this method in the field of infertility. 3-D US is useful in patients scheduled for serial ovarian monitoring in whom planar reformatted sections allow more accurate and objective volumetric assessment of the leading follicles, which are not always spherical. Ovarian volume measurements by 3-D US contribute to accurate diagnosis of polycystic ovarian syndrome and prediction of the response to stimulation and estimation of the risk of ovarian hyperstimulation. Transvaginal ultrasound directed follicular aspiration and embryo transfer under 3-D US guidance may improve the operator's spatial evaluation and allows precise follicular and/or catheter tip location during the course of interventional procedures. The use of 3-D color/power Doppler US after injection of saline solution and/or echo enhancing contrast medium produces high diagnostic accuracy for visualization of the uterine cavity and Fallopian tubes. By providing multiple tomographic sections of the uterine cavity, uterine causes of infertility such as congenital uterine anomalies, submucous leiomyoma, and/or adhesions become easily visible. Quantification of the endometrial volume by 3-D US in combination with blood flow studies contributes to assessment of the endometrial receptivity and may have the potential to predict pregnancy rates in assisted reproductive techniques.