Risk of torsion and malignancy by adnexal mass size in pregnant women.

OBJECTIVE

To investigate risks of torsion and malignancy by adnexal mass size during pregnancy.

DESIGN

Retrospective review of medical records.

SETTING

General university hospital and healthcare center.

POPULATION

Four hundred and seventy women who underwent surgery for adnexal masses during pregnancy between 2002 and 2009.

MAIN OUTCOME MEASURES

Rate of torsion and malignancy according to mass size classified into four groups: <6, 6-10, 10-15 and ≥15 cm.

RESULTS

Torsion was encountered in 55 patients (11.7%) and malignancy was confirmed in 20 (4.3%). A mass size of 6-10 cm had a significantly higher risk of torsion than a mass <6 cm (odds ratio 2.68, 95% confidence interval 1.33-5.40, p=0.006). Masses ≥15 cm had an approximately 12-fold higher risk of malignancy compared with masses <6 cm (odds ratio 12.36, 95% confidence interval 2.90-52.67, p=0.001). However, for masses of 10-15 cm, the risks of both torsion and malignancy were not higher than those of masses <6 cm.

CONCLUSIONS

Risks of torsion and malignancy are not directly proportional to increasing mass size in pregnant women. Physicians should be aware of a high risk of malignancy in women with an adnexal mass of over 15 cm. However, if a mass is smaller, the size should not be considered as a single independent factor in a decision for surgery.