Van Wyk Grumbach syndrome (VWGS) is characterized by untreated severe hypothyroidism, isosexual precocious puberty, multiple ovarian cysts and delayed bone age. Although it is extremely rare, it is important to recognize before the unnecessary ovarian surgeries because of its curability with a simple thyroid hormone replacement. Here, we reported a 5-year-and-3-months old female patient presented with precocious menarche and diagnosed as VWGS with primary hypothyroidism, isosexual precocious puberty and multiple ovarian cysts. Following L-thyroxine replacement therapy, all complaints and hormonal abnormalities resolved and finally, the multicystic mass structure in the ovaries disappeared completely. The diagnosis of VWGS should be kept in mind because simple L-thyroxine replacement completely resolves symptoms and abnormalities and prevents unnecessary investigations for malignancies and surgeries.

Keywords: Van Wyk Grumbach syndrome, hypothyroidism, precocious puberty