A 43-year-old nulliparous woman presented to a dermatology clinic in Montreal, Quebec, Canada, in 2015 with swelling and pain in the umbilical area which worsened and occasionally bled during menstruation. The onset of these symptoms coincided with the discontinuation of oral contraceptive pills, which she had been taking for the last seven years. The patient complained of dysmenorrhoea and had no history of abdominal or pelvic surgeries. Upon clinical examination, multiple ill-defined bluish erythematous papules were noted in and surrounding the umbilicus [Figure 1]. A skin biopsy showed glandular proliferation with hemosiderin deposition and myometrial stroma, consistent with a diagnosis of endometriosis [Figure 2]. A gynaecological evaluation revealed an ovarian cyst. She was treated with progestin which relieved the dysmenorrhoea and resulted in the regression of both the ovarian cyst and her umbilical symptoms. As most of the remaining umbilical nodules were small and remained asymptomatic, the patient did not wish to have them surgically removed.