Spontaneous rectus sheath hematoma in pregnancy and a systematic anatomical workup of rectus sheath hematoma: a case report.

Background: Rectus sheath hematoma is a rare clinical diagnosis, particularly in pregnancy. Due to unspecific symptoms, misdiagnosis is likely and could potentially endanger a patient as well as her fetus.
Case Presentation: A 26-year-old white woman presented with mild right-sided abdominal pain, which increased during palpation and movement, at 26 + 3 weeks' gestational age. Ultrasound imaging initially showed a round and well-demarcated structure, which appeared to be in contact with her uterine wall, leading to a suspected diagnosis of an infarcted leiomyoma. However, she reported increasing levels of pain and laboratory tests showed a significant drop in her initially normal hemoglobin level. A magnetic resonance imaging scan finally revealed a large type III rectus sheath hematoma on the right side. Because of progressive blood loss into her rectus sheath under conservative therapy, with a significant further decrease in her hemoglobin levels, surgical treatment via right-sided paramedian laparotomy was initiated. During the operation the arterial bleed could be ligated. She eventually achieved complete convalescence and delivered a healthy newborn spontaneously after 40 weeks of gestation.
Conclusion: This case report highlights the clinical and diagnostic features of rectus sheath hematoma and shows the anatomical aspects of the rectus sheath, simplifying early and correct diagnosis.