A 26-year-old white woman (II gravida/I para) presented at the gestational age of 26 + 3 weeks with right-sided abdominal pain. The course of her pregnancy up to this point was normal. There had been no pre-existing illnesses. She merely reported a flu-like infection associated with severe coughing fits the week before, which was almost in complete remission. She had not received any anticoagulant therapy and had no indications for any other anticoagulant abnormalities. No trauma could be recollected and there had been no further surgical interventions. On admission, she presented hemodynamically stable with vital signs within normal limits. Physical and pelvic examinations appeared normal apart from moderate maternal obesity and a mild tenderness in her right upper quadrant which increased when moving. Ultrasound revealed a normal progression of pregnancy, regular percentiles of fetal growth, and a normal Doppler ultrasound state. The placenta was located at the rear aspect of her uterus without indications for a retroplacental hematoma or acute abruptio placentae. However, a 9.16 × 9.73 cm, round, well-demarcated, and partly hypoechoic/isoechoic structure, which appeared to be in contact with her uterine wall but clearly separated from the placenta, was identified. Its inhomogeneous internal structure led to the suspected diagnosis of an acute symptomatic infarcted pedunculated myoma. As a possible differential diagnosis we considered a hematoma of unknown origin. However, initial laboratory findings were consistent with our first hypothesis and did not show a typical HELLP (hemolysis, elevated liver enzymes, low platelet count) constellation or other severe abnormalities. Her hemoglobin (Hb) level was 11.8 g/dl and her level of C-reactive protein (CRP) was slightly elevated at 20.4 mg/l. Furthermore, her coagulation parameters appeared to be normal. We initiated analgesic therapy with acetaminophen and piritramide as well as intramuscular dexamethasone injection as a fetal respiratory distress prophylaxis. Initially, her abdominal pain subsided mildly and cardiotocography (CTG) monitoring showed physiological values. On day 2 after admission, she reported an acute exacerbation of her abdominal pain. Sonographic reevaluation indicated an increase in size of the aforementioned structure. Laboratory findings showed a significant decrease in Hb to 8.1 g/dl, negating our initial diagnosis. We suspected an acute hematoma of unknown origin or an abdominal bleed and initiated an emergency magnetic resonance imaging (MRI) scan, which showed a RSH measuring 11 × 12 × 20 cm that was located at the right side of her anterior abdominal wall. We started conservative treatment with analgesics and balanced intravenous fluids. After a few hours she developed severe and progressive pain. Repetitive laboratory tests showed a further decrease in Hb levels. She developed hypotension, indicating surgical exploration by right-sided paramedian laparotomy. After incision of the anterior fasciae of her rectus sheath the hematoma was recovered, measuring approximately 1000 ml of fresh and coagulated blood. At the caudal aspect a sputtering hemorrhage of the inferior epigastric artery was found and both ends were ligated. Two 16G drains were placed and put under suction. A total of 4 units of packed red blood cells were transfused. Intraoperative fetal monitoring was conducted by transabdominal ultrasound and showed normal fetal heart rates. After the procedure her Hb levels remained stable and her complete convalescence was swift. She was discharged on day 5 post surgery. Fetal parameters appeared to be normal. At 40 weeks’ of gestational age she underwent normal spontaneous vaginal delivery under intensified peripartum controls.