Ovarian torsion due to ovarian hyperstimulation syndrome diagnosed by sonographic whirlpool sign in the first trimester of pregnancy: A case report

Ovarian torsion during pregnancy is a rare condition that needs prompt diagnosis and detorsion in order to preserve ovarian function. Diagnosing ovarian torsion is a difficult procedure especially in pregnant cases since radiation exposure should be avoided. Detecting the whirlpool sign by ultrasonography is a highly useful technique as it is noninvasive, less time-consuming, and radiation-free. Here is a case of ovarian torsion due to ovarian hyperstimulation syndrome diagnosed solely by sonographic features and in which laparoscopic detorsion was promptly performed. A 26-year-old woman in her sixth week of pregnancy visited a tertiary hospital with sudden onset lower abdomen pain. Transvaginal ultrasound detected an 8 cm left ovary and a whirlpool sign between the uterus and left ovary. Ovarian torsion was suspected and laparoscopic surgery was performed. Intraoperatively, an enlarged left ovary was twisted at 540° involving the left fallopian tube. After detorsion, bilateral ovaries were preserved and the postoperative course was uneventful. Ovarian torsion was suspected solely by ultrasonographic features which led to surgical detorsion quickly, resulting in the preservation of bilateral ovaries. Detecting the whirlpool sign when ovarian torsion is suspected is useful, especially in pregnant women.