Why does Anorchia happen?
Last updated September 7, 2026.
**Anorchia happens when both testicles form early in fetal development and are then lost before birth, most often because their blood supply twists shut.** Doctors often call this vanishing testes syndrome. The early testes worked long enough to build male genitals and internal anatomy, so the loss usually happened later in pregnancy rather than at conception. A smaller number of cases trace to genetic changes that affect how the testes form, and rarely the condition runs in a family. Nothing a parent ate, took, or did in pregnancy is known to cause it. Confirming anorchia takes hormone blood tests, chromosome testing, and imaging, because an undescended testicle hiding in the abdomen looks the same from the outside.
What to do
- Confirm before concluding: An empty scrotum is far more often an undescended or retractile testicle than true anorchia, so get imaging and hormone testing before accepting a diagnosis.
- Ask for the right blood work: Anti-Mullerian hormone, inhibin B, testosterone, LH, and FSH together tell your clinician whether any working testicular tissue is present.
- Plan hormone replacement early: Testosterone therapy started around the usual age of puberty supports bone strength, muscle, voice change, and sexual development, so ask for an endocrinology referral.
- Talk about fertility honestly: Anorchia means no sperm production, so discuss donor sperm, adoption, and counseling options with your clinician when family planning matters to you.
- Consider genetic input: If other relatives are affected or other birth differences are present, chromosome and gene testing can clarify the cause and what it means for family members.
- See a clinician for new changes: Sudden testicular pain, swelling, or a groin lump at any age needs same-day care, since torsion is an emergency.