Torted Fibroid: A Cause of Acute Abdomen in Pregnancy

A 34-year-old woman (G2, P1) presented to the birthing unit at 35 weeks gestation with 2 days of periumbilical pain and a lump. She had no nausea or vomiting and no change in bowel habits. Her surgical background included open inguinal hernia repairs in childhood. Her obstetric history was significant for the vaginal delivery of a healthy baby 3 years previously. Her observations were normal. She had a gravid uterus consistent in size with her gestational age, and a tender, firm, mildly erythematous lump at her umbilicus. An abdominal ultrasound demonstrated a 50 × 46 mm heterogeneously echogenic mass contained within the anterior abdominal wall, the appearance of which was consistent with adipose tissue/omentum (Figures 1 and 2). Cardiotocography (CTG) was unremarkable. The working diagnosis was an incarcerated umbilical hernia. The patient underwent a general anesthetic, and a transverse supra-umbilical incision was made. Dissection onto the mass revealed a pedunculated subserosal uterine leiomyoma that arose from the anterior uterine wall and had undergone torsion (Figure 3). There was no hernia. The fibroid was excised at its base using an energy device, and the abdominal wall fascia was closed with an absorbable suture. Histopathology confirmed a 50 × 45 × 20 mm leiomyoma with extensive infarction and no malignant features. Fibroids are the most common pelvic tumor in women, and the prevalence in pregnancy is estimated between 1.5% and 10% 1, 2. In women over 30, the prevalence is at least 20% across most ethnic groups 2-4. Given that maternal age in Western countries is increasing and fibroids tend to enlarge during the first trimester, fibroids in pregnancy may become a more relevant clinical problem 5, 6. While most fibroids are asymptomatic in pregnancy, they can increase the risk of placental abruption, postpartum hemorrhage, and preterm labor, particularly if submucosal or intramural 4, 7. Pain is the most common presenting symptom; this may relate to rapid growth of the fibroid, leading to reduced tissue perfusion and necrosis 4, 8. Myomectomy in pregnancy is generally reserved for those with an acute abdomen or concern for malignancy. A recent systematic review of myomectomy in pregnancy examined the outcomes of the 97 patients presented in the literature 9. The median gestational age at surgery was 16 weeks (range 6–26), and 78% of patients had myomectomy via laparotomy. Reassuringly, only five cases out of 97 reported miscarriages, and the mean gestational age at delivery was 37.2 weeks. Our case appears to be the first in the literature presenting with a torted fibroid and palpable mass, mistaken for an incarcerated hernia. It also appears to be the only case presenting in the third trimester. Our patient had a good postoperative recovery and achieved a spontaneous vaginal birth of a healthy baby girl at term. Symptomatic fibroids in pregnancy are a rare presentation of acute abdomen but should be considered as a differential diagnosis, particularly in women over the age of 30, or with a personal history of fibroids. Myomectomy can be performed safely for subserosal fibroids with minimal maternal or fetal complications. The authors have nothing to report. Open access publishing facilitated by University of New South Wales, as part of the Wiley - University of New South Wales agreement via the Council of Australian University Librarians. The patient provided written consent for her case to be published. The authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.