Acute Uterine Torsion Masquerading as Fibroid Degeneration in a High-Risk Pregnancy: A Case of Diagnostic Surprise

Abstract

Uterine torsion during pregnancy is a rare and life-threatening condition that is frequently misdiagnosed due to nonspecific symptoms and imaging limitations. This case report describes a 32-year-old third gravida (G3, P0+2) with recurrent pregnancy loss, having a 16.9 cm uterine fibroid and hypertrophic cardiomyopathy (managed with bisoprolol), who presented at 24 weeks with severe abdominal pain. Although her vitals were stable, a markedly elevated C-reactive protein (CRP) (245 mg/dL) raised concern for acute pathology. Initial ultrasound incorrectly localized the fibroid to the left, but exploratory laparotomy revealed a 180-degree uterine torsion with contralateral fibroid position, revising the diagnosis from fibroid degeneration to this rare emergency, leading to detorsion and myomectomy. At 30 weeks' gestation, cervical insufficiency (a short cervix measuring 0.5 cm with funneling) was successfully managed with an Arabin pessary and weekly 500 mg injections of hydroxyprogesterone, prolonging the pregnancy to 34 weeks and resulting in an outlet forceps delivery of a healthy 1.9 kg infant. This case highlights the importance of surgical exploration when clinical suspicion contradicts imaging findings, the feasibility of pregnancy-preserving surgery for uterine torsion, and the effectiveness of combined mechanical-hormonal therapy for cervical insufficiency following complex uterine interventions. Multidisciplinary care was critical to manage overlapping high-risk factors, including fibroids, cardiac disease, and preterm cervical changes, ultimately leading to a favorable outcome.

Keywords: arabin pessary; myomectomy in pregnancy; preterm labor and obstetric care; uterine fibroid in pregnancy; uterine torsion.

Figure 1. Ultrasonographic findings at 22 weeks of gestation complicated by a giant uterine fibroid.

(A) Composite image showing fetal biparietal diameter (BPD) and femur length (FL) measurements, marked by double white arrows. (B) Transabdominal ultrasound demonstrating a large intramural fibroid (FIGO type 5) measuring 18.48 × 12.67 × 16.21 cm with heterogeneous echotexture, also marked by double white arrows. The images highlight the technical challenges of sonographic fetal monitoring in the presence of a giant fibroid. Notably, the fibroid’s location and size did not impair standard biometric assessments, underscoring the importance of meticulous imaging planes to distinguish fetal structures from fibroid tissue.

Figure 2. Composite image (A) demonstrates the gestational sac (large white arrow), which was initially misdiagnosed as a fibroid with degeneration, and (B) shows the fundal fibroid (double small white arrows) after extension of the incision and application of a Foley catheter as a tourniquet to minimize blood loss, as vasopressin is contraindicated in the presence of a live fetus.

Figure 3. The post-myomectomy image shows successful preservation of the pregnancy, with triple small white arrows indicating the final repair site of the myomectomy scar.

Figure 4. Image of the Arabin pessary (Dr. Arabin, Witten, Germany) inserted per vaginam for the prevention of preterm labor in the context of a short cervix at 30 weeks' gestation.

The image was captured by the authors and is published under a Creative Commons license.