Spontaneous ovarian hyperstimulation syndrome in a nonpregnant female patient: a case report and literature review

Spontaneous ovarian hyperstimulation syndrome (sOHSS) usually occurs in patients with a spontaneous ovulation cycle, especially in those with multiple pregnancies combined with hypothyroidism and polycystic ovary syndrome. sOHSS rarely occurs in women who are not pregnant. A 23-year-old woman with obvious abdominal distension visited our hospital. The patient was not pregnant and had not undergone controlled superovulation. Apart from abdominal distension, the patient denied any symptom of obvious incentives, abdominal pain, abnormal vaginal bleeding, or drainage. Biochemical analysis showed a high carbohydrate antigen-125 level and low total protein and albumin levels. Abdominal ultrasound and computed tomography showed a large amount of ascites and cystic uneven masses with an irregular shape in the area of the ovaries and fallopian tubes. Post-surgical histopathology indicated the diagnosis of sOHSS. Wedge resection of both ovaries was performed. Symptomatic treatment was further performed and the patient recovered well. Our findings indicate that sOHSS can occur in women who are not pregnant. Additionally, besides the follicle-stimulating hormone receptor gene mutation hypothesis, the pathogenesis of sOHSS should be further studied.