Van Wyk–Grumbach Syndrome (VWGS) is an uncommon clinical entity arising from long-standing untreated juvenile hypothyroidism. It is characterized by hallmark features such as isosexual precocious puberty, delayed skeletal maturation, and impaired linear growth, first delineated by Van Wyk and Grumbach in 1960. Recognizing this syndrome is crucial to prevent unnecessary gynecological interventions. While multicystic ovarian enlargement is the typical presentation, uteromegaly is exceedingly rare. We present a unique case highlighting this atypical manifestation.

A 24-year-old female presented with progressive abdominal distension, episodic, and throbbing abdominal pain. Symptoms had persisted for 14 years, with significant worsening over the past year. Clinical findings included short stature, obesity (40 kg, 120 cm; BMI 27.7), generalized edema, irregular and prolonged menstruation since menarche at 14 years, and recurrent menorrhagia for five years. Developmental history revealed growth arrest and absence of pubertal progression since age 10, while her twin sibling demonstrated normal growth. Physical examination showed delayed secondary sexual characteristics. Radiographic evaluation confirmed delayed bone age. Laboratory studies revealed severe hemoglobinemia (5.8 g/dL), markedly elevated TSH (>100 μIU/mL), suppressed FT4 (0.04 ng/dL), low LH (0.16 mIU/mL), and low–normal FSH (5.15 mIU/mL). Imaging demonstrated uteromegaly and hypoplastic thyroid lobes.

The constellation of severe hypothyroidism, short stature, delayed bone age, menstrual abnormalities, and uterine enlargement supported the diagnosis of Van Wyk–Grumbach Syndrome. The patient was commenced on L-thyroxine at a dose of 50 mcg daily, with plans for gradual titration.

Conclusions: This case emphasizes the importance of vigilance for VWGS in unusual presentation of hypothyroidism. The presence of uteromegaly instead of the more common multicystic ovarian morphology underscores the spectrum of thyroid hormone activities in reproduction system. Early recognition and appropriate thyroid hormone replacement are pivotal for reversing gynecologic and growth manifestations.