Hypothyroidism-induced spontaneous ovarian hyperstimulation syndrome

A 17-year-old unmarried female presented to the gynecology department with complaints of persistent lower abdominal pain and distension lasting for 25 days.

On examination, the lady elicited lower abdominal tenderness. Blood and biochemical tests revealed a low hemoglobin level (9 mg/dl), significantly elevated TSH level (486 µIU/ml), and decreased free T4 level (0.35 ng/dl), indicative of primary hypothyroidism. 

Pelvic MRI displayed bilateral markedly enlarged ovaries with variable-sized cysts exhibiting thin internal septations. Some cysts exhibited hyperintense contents on T1-weighted imaging with blood-fluid levels on T2-weighted imaging. The right ovary measured 12 x 19 x 13 cm³ (AP x TR x CC), while the left measured 10 x 14 x 11 cm³ (AP x TR x CC), accompanied by mild free fluid in the pelvis. Tumor markers were within normal ranges, including – CA-125, alpha-fetoprotein, and beta HCG. 

Consequently, the patient commenced thyroxine treatment at 100 µg/day, resulting in symptomatic improvement within a week. 

Subsequent follow-up after one month showed alleviation of abdominal symptoms, with a reduced TSH level of 22 µIU/ml. Ultrasound evaluation demonstrated a notable decrease in bilateral ovarian volume and cyst size. 

Treatment continuation led to near-complete resolution of ovarian enlargement and cystic changes after three months, with normal ovarian volume evident on follow-up ultrasound. The patient's TSH level decreased to 14 µIU/ml. 

Given the clinical, biochemical, and imaging findings, a diagnosis of spontaneous ovarian hyperstimulation syndrome (OHSS) in primary hypothyroidism was proposed. The patient received ongoing medication and regular follow-up, highlighting the occurrence of spontaneous OHSS in non-pregnant women without ovulation induction therapy. 

Clinicians should consider this rare diagnostic possibility in cases of unexplained bilateral cystic ovarian masses, emphasizing the importance of evaluating for hypothyroidism in spontaneous OHSS cases. The comprehensive evaluation of clinical, radiological, and laboratory findings facilitates prompt diagnosis and management.

Source: Pail SM, Bagri N, Ghas RG. New Indian J OBGYN. 2023;10(1):229-32.