The clinical characteristics and sonographic findings of maternal ovarian torsion in pregnancy.

OBJECTIVE

To investigate the incidence, risk factors, and sonographic findings of maternal ovarian torsion in pregnancy.

DESIGN

Retrospective study.

SETTING

Department of Obstetrics/Gynecology of a tertiary referral center.

PATIENT(S): Thirty-three pregnant women with 38 episodes of surgically proven torsion between the years 1993 to 2007.

INTERVENTION

Surgical confirmation and treatment of torsion.

MAIN OUTCOME MEASURE(S): Clinical and sonographic findings of ovarian torsion in pregnancy.

RESULTS

Sixteen (48.5%) pregnancies were conceived by ovulation induction or in vitro fertilization. Twenty-one torsion events occurred in the first trimester (55.3%) versus 13 (34.2%) and 4 (10.5%) in the second and third trimester, respectively. All patients were admitted with abdominal pain, whereas 22 (57.9%) reported nausea/vomiting. The preoperative ultrasound examination showed unilocular ovarian cysts in 15 (39.5%) cases, multicystic ovaries in 14 (36.8%), and normally appearing ovaries in 9 (23.7%) cases. The multicystic ovary was more common in the first trimester torsion, whereas the "normal" appearing ovary was more common in the second and third trimester torsion (47.6% vs. 23.5% and 14.3% vs. 35.3%, respectively). The median duration from admission to surgery was 6 hours (range, 1 hour to 3.7 days), being significantly shorter in the first trimester.

CONCLUSION(S): Ovarian torsion in pregnancy is more common in the first trimester, and induction of ovulation is a major risk factor.