A ten year and two month-old girl with Down syndrome was admitted due to two episodes of vaginal bleeding with one month interval. She was diagnosed and treated for acute megacaryocytic leukemia diagnosed at two years of age and was in remission for seven years. She was also being followed routinely for hypothyroidism, epilepsy, celiac disease and osteopenia. On physical examination, she had bilateral nipple and areolar complex. There was no palpable glandular tissue. Gonadotropin (FSH 3.3 mIU/ml, LH 4.77 mIU/ml) and estradiol (E2 93 pg/ml) levels were within pubertal range. On the pelvic ultrasonography, the ovaries and uterus were at pubertal size. Breast tissue was not detected by ultrasonography. Her bone age was 13-14 years. It was considered that pubertal onset and progression have not been recognized by the family and her doctors due to bilateral amazia till menarche. In the literature, we could not find any report on an association of Down syndrome and bilateral amazia. If diagnosis of true puberty has been confirmed by hormonal analysis in a girls admitted with vaginal bleeding without breast development, a rare condition, congenital bilateral amazia must be taken into consideration.

Keywords: puberty, amazia, Down syndrome