517 müllerian duct anomalies were detected in 10.352 patients (4.99%). The distribution of different Müllerian anomalies observed is showed in the next figure (Figure 2).

Fig.: FIGURE 2. DISTRIBUTION OF MÜLERIAN DUCT ANOMALIES.

a) Arcuate uterus was the most common malformation observed (n= 289; 59.8% of all müllerian ducts anomalies). It consists of mild indentation of endometrium at uterine fundus because of near complete resorption of the utero- vaginal septum, with normal external uterine contour (Figure 3). It is considered by many authors as an anatomic variant.

Fig.: Figure 3. ARCUATE UTERUS. Sagittal (a), transverse (b), coronal oblique 2D (c), and coronal oblique reconstructed 3D (d) endovaginal US image demonstrate fundal indentation and normal external uterine contour.

b) Septate uterus was second most common anomaly found (n= 95; 18.3%). It results from partial (Figure 4a) or complete (Figure 4b) failure of resorption of the utero-vaginal septum. The external uterine contour is normal.

Fig.: FIGURE 4a. PARTIAL SEPTATE UTERUS. Sagittal (a), transverse (b), coronal oblique (c) 2D; and 3D reconstructed coronal oblique (d) endovaginal US images of a partial uterine septum demonstrate mild indentation of the uterine fundus with normal external contour.

Fig.: FIGURE 4b. COMPLETE SEPTATE UTERUS. Sagittal (a), transverse (b), coronal oblique (c) 2D; and 3D reconstructed coronal oblique (d) endovaginal US images of a partial uterine septum show convex external uterine contour with vertical septum extending to external uterine os.

c) Bicornuate uterus: were found 74 (14.4%), and it results from incomplete fusion of the Müllerian ducts. There is a cleft of the external fundal uterine contour (Figure 5).

Fig.: FIGURE 5. BICORNUATE UTERUS. Sagittal (a), transverse (b), coronal oblique (c) 2D; and 3D reconstructed coronal oblique (d) endovaginal US images demonstrate external fundal cleft with wide divergence of endometrial cavities.

d) Didelphys uterus is the result of nearly complete failure of fusion of the Müllerian ducts, developing two hemiuterus and cervix without communication (Figure 6). We found 20 of them (3.8%).

Fig.: FIGURE 6. DIDELPHYS UTERUS. Sagittal (a), transverse (b), coronal oblique (c) 2D; and 3D reconstructed coronal oblique (d) endovaginal US images show complete duplication of uterine horns and cervices.

e) Unicornuate uterus takes place by the failure of one Müllerian duct development, which can persist as a rudimentary horn that communicates or not with the endometrium of the contralateral horn (Figures 7a, 7b).

Fig.: FIGURE 7a. UNICORNUATE UTERUS. Sagittal (a), transverse (b), coronal oblique (c)2D; and 3D reconstructed coronal oblique (d) endovaginal US images demonstrate uterus with abnormal lenticular shape of endometrial cavity.

Fig.: FIGURE 7b. UNICORNUATE UTERUS WITH RUDIMENTARY HORN. Sagittal (a), transverse (b), coronal oblique (c) 2D; and 3D reconstructed coronal oblique (d) endovaginal US images show unicornuate uterus with rudimentary horn. Cavitary rudimentary horn is not communicated with the endometrium of the contralateral horn.

f) Diethylstilbestrol (DES) – exposed uterus: a T-shaped configuration of endometrial cavity is the most commonly associated abnormality. We found 4 cases.

Nowadays MR is very useful to identify these anomalies because it can visualize fundal external contour and utero-vaginal septum (Figure 8). MR allows evaluating ovaries and associated pelvic or renal anomalies, but it is less accessible and more expensive than ultrasound. In addition, 3D ultrasound has multiplanar capability, similar to MR.

Fig.: FIGURE 8. MR COMPLETE SEPTATE UTERUS. Coronal- oblique T2 weighted FSE image shows a complete septum (pink arrow) extending to the external os. The fundus has a convex external contour (blue arrow).

Hysterosalpingography (HSG) is a moderately invasive and radiating study, although it is reemerging because it is the best method for evaluating the Fallopian tubes (Figure 9). 2D and 3D ultrasound do not radiate and are non-invasive techniques.

Fig.: FIGURE 9. HYSTEROSALPINGOGRAPHY OF AN ARCUATE UTERUS. This study demonstrates a depression of the uterine fundus, and opacification of both Fallopian tubes.

Laparoscopy and hysteroscopy (Figure 10) are invasive diagnostic procedures reserved for surgical patients.

Fig.: FIGURE 10. LAPAROSCOPY AND HYSTEROSCOPY OF A BICORNUATE UTERUS. Laparoscopy image (a) shows two horns with wide divergence. Hysteroscopic image demonstrates two endometrial cavities within each horn.