Ovarian torsion in early pregnancy

Case contributed by Dr Alexandra Stanislavsky


1 week history of severe left iliac fossa pain. 12 weeks pregnant. Initial ultrasound was normal.

Patient Data

Age: 30 years
Gender: Female

Gravid uterus, with a singleton mobile early gestation, not specifically assessed.

Normal right ovary, located posterolaterally relative to the uterus.

Left ovary is markedly edematous, T2 hyperintense with T2 shine through on DWI/ADC. It is located in the pouch of Douglas and is enlarged to approximately 50cc.  A corpus luteum is identified within this, as was seen on the preceding ultrasound (not shown).

Edematous, T2 hyperintense left fallopian tube is identified, best appreciated on the sagittal T2 images.

An ultrasound was performed for correlation with the initial ultrasound from 1 week ago, which was normal (not shown).  Current ultrasound confirms a edematous, enlarged left ovary (volume 54cc) with multiple small follicles and a corpus luteum displaced to the periphery. The vascular pedicle is also engorged, and there is a small amount of free fluid in the Pouch of Douglas. 

Interestingly, arterial flow with normal waveforms was detected in both the ovary and its pedicle, suggesting either an incomplete torsion, or an element of torsion-detorsion.

Case Discussion

MRI and ultrasound appearance of ovarian torsion in a 12 week pregnant patient. Note that the affected ovary contains the corpus luteum, and this is an established risk factor for torsion in early pregnancy. The presence of arterial flow within the ovary suggest either an incomplete torsion, or a torsion-detorsion scenario.  

The delayed presentation (with initial US normal) highlights the difficulty sometimes encountered in making the diagnosis, particularly in the setting of pregnancy, and with intermittent detorsion. A high index of suspicion should be maintained, particularly if there is tenderness or mild swelling of an ovary containing a corpus luteum in early pregnancy.

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