meromelia

birth defect

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Last updated

June 30, 2026

Quick Summary

Meromelia is a birth defect characterized by the congenital absence or malformation of extremities. This condition arises from errors in limb bud development between the fourth and eighth weeks of intrauterine life.1

Different forms of meromelia include:
* Amelia: Complete absence of limbs.1
* Ectromelia: Absence of one or more extremities.1
* Phocomelia: Underdeveloped or missing upper limb parts, with the lower limb attached directly to the trunk.1
* Hemimelia: Well-formed upper limb but rudimentary or absent lower limb.1
* Sirenomelia: Fused legs with malformed bones and absent anal and urinary openings.1

Agenesis, the failure of an organ to develop, can also affect long bones, leading to conditions like meromelia. Exposure to substances like thalidomide during pregnancy has been linked to these malformations. Treatment may involve prosthetics, training, or surgery for minor defects.21

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agenesis
…also may occur, called variously meromelia (absence of one or both hands or feet), phocomelia (normal hands and feet but absence of the long bones), and amelia (complete absence of one or more limbs).
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…also may occur, called variously meromelia (absence of one or both hands or feet), phocomelia (normal hands and feet but absence of the long bones), and amelia (complete absence of one or more limbs).
Read More