T-shaped uterus

T-shaped uterus refers to a specific radiographic appearance of the endometrial cavity.

Pathology

It is the most commonly associated abnormality from in utero diethylstilbestrol (DES) exposure, seen in 31% of exposed women. It is classified as a class VII Müllerian duct anomaly.

Background

DES is a synthetic estrogen that was introduced in 1948 and was prescribed for women experiencing recurrent spontaneous abortions, premature deliveries, and other pregnancy complications. By increasing the synthesis of placental steroidal hormones, DES was thought to decrease the frequency of pregnancy loss.

Radiographic features

Hysterosalpingogram (HSG)

Typically shows a narrowed irregular endocervical canal. The opacified endometrial cavity appears small, with a shortened upper uterine segment, resulting in the characteristic T-configuration.

Complications

In utero exposure to DES was shown to be associated with clear cell carcinoma of the vagina/cervix. The use of the drug was therefore abruptly discontinued in 1971 (incidence 0.14-1.4 per 1000 women exposed).

Differential diagnosis

Considerations include:

• infantile: prepubertal uterus
• this appearance can also be observed in adult women with severe estrogen deficiencies in which the uterus fails to attain postpubertal proportions because of the absence of normal estrogen stimulus  
• it may be seen in patients taking oral contraceptives for long periods of time

Siehe auch:

• Müllerian duct anomaly classification