MONDO_0009461 (spermatogenic failure 5) is a male infertility due to sperm disorder characterized by the presence, in sperm, of a very high percentage of spermatozoa with enlarged head, irregular head shape, multiple flagella, and abnormal midpiece and acrosome. It is generally associated with severe oligoasthenozoospermia and a high rate of sperm chromosomal abnormalities (polyploidy, aneuploidy). Also known as: SPGF5, macrocephalic sperm head syndrome, macrozoospermia with multiflagellar polyploid spermatozoa, male infertility due to large-headed multiflagellar polyploid spermatozoa, male infertility due to macrozoospermia, male infertility with large-headed, multiflagellar, polyploid spermatozoa, spermatogenic failure type 5.