Achondroplasia (ACH) – 1 in 20,000 to 30,000 Births

What is ACH?: Achondroplasia is the most common condition affecting bone growth and occurs in about 1 out of every 20,000 to 30,000 births. It is a genetic condition that causes short stature with an average adult height of around 4 feet. People with achondroplasia often have a larger head, short upper arms, limited elbow Read.