Background: Adenovirus infection is usually mild in presentation. However during pregnancy, the course can be more severe., Case: A 21-year-old woman in her second pregnancy presented with abdominal pain, vomiting, and fevers at 34 weeks and 4 days of gestation. Her respiratory pathogen panel on nasopharyngeal secretions was positive for adenovirus. Electrolytes were notable for hypomagnesaemia and persistent hypokalemia (nadir of 2.6 mmol/L) despite repletion but otherwise unremarkable. During her course, she developed rhabdomyolysis. During routine fetal monitoring at 35 weeks and 6 days of gestation, prolonged fetal bradycardia was identified, and an emergency caesarean delivery was performed. The infant had no clinical or laboratory evidence of adenovirus infection. The patient had a protracted clinical course but recovered with supportive care., Conclusion: Adenovirus can present with severe complications in a pregnant woman including hypokalemia and rhabdomyolysis. The mainstay of treatment is supportive care and monitoring of electrolyte abnormalities and renal function., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2020.)