Ultrasound assessment of the pelvic organs in girls of the first year of life (literature review)

Ultrasound is the primary diagnostic modality for evaluating pelvic organ pathology in young girls, with ovarian cysts being the most commonly encountered condition. Accurate normative reference values for the size of reproductive organs, along with knowledge of their physiological features during the first months of life, are essential for detecting abnormalities and determining appropriate management strategies. Data obtained over the past decade has demonstrated that ovarian follicle size in girls during the first year of life is larger than previously assumed. Moreover, the dimensions of the uterus and ovaries change significantly throughout this period, most likely reflecting changes  in gonadotropin levels during *mini-puberty*.  The review summarizes ultrasound-based data on the structure and size of pelvic organs in healthy female infants during the first months of life, describes the ovarian cysts features and different management approaches at this age, and discusses the main causes and possible consequences of hypothalamic-pituitary-gonadal axis activation after birth (*mini-puberty*).

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