Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Leydig cell hypoplasia ?
    ### Response:
    Leydig cell hypoplasia is a condition that affects male sexual development. It is characterized by underdevelopment (hypoplasia) of Leydig cells in the testes. Leydig cells secrete male sex hormones (androgens) that are important for normal male sexual development before birth and during puberty.
    