Hypoplasia is a medical condition that refers to the incomplete development or underdevelopment of an organ or tissue due to an inadequate or below-normal number of cells. It is similar to aplasia, but less severe. Hypoplasia can affect any tissue or organ in the body and can be present at birth (congenital) . The symptoms of hypoplasia vary depending on the tissue that is affected. Some common types of hypoplasia include:

• Testicular hypoplasia (seen in Klinefelters syndrome)
• Optic nerve hypoplasia
• Enamel hypoplasia (also known as Turners hypoplasia)
• Cardiac hypoplasia (hypoplastic left heart syndrome and right hypoplastic heart syndrome)
• Thymus hypoplasia (DiGeorge syndrome)
• Uterine hypoplasia (also known as naïve uterus or infantile uterus)

The symptoms of hypoplasia depend on the tissue that is affected. For example, optic nerve hypoplasia can lead to visual difficulties, nystagmus, and strabismus, while enamel hypoplasia can make the teeth hypersensitive to heat or cold. Treatment for hypoplasia depends on the underlying disorder and the severity of symptoms. Generally, treatment is symptomatic and supportive.