Rare diseases · Sign or symptom
Hypoplastic male external genitalia
Small male external genitalia
HP:0000050
What it means
Underdevelopment of part or all of the male external reproductive organs (which include the penis, the scrotum and the urethra).
Rare diseases that can present with this5
Sometimes5–29%
1The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Also called: Hypoplastic male genitalia · Underdeveloped male genitalia
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Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.