Dihydrotestosterone, or DHT, is a hormone that plays a critical role in male sexual development, including the production of sperm cells in the testes. A lack of DHT will usually prevent a man from fathering children. However, DHT is not the only factor that influences sexual development, and researchers have found cases of DHT-deficient men with normal sperm.
Significance
The National Cancer Institute, a division of the National Institutes of Health, says dihydrotestosterone is responsible both for primary and secondary male sex characteristics. Primary sex characteristics involve the development of reproductive organs, specifically the penis and testes. Secondary characteristics are the changes that show up in puberty, such as the emergence of facial and body hair, a deepening of the voice, and an increase in muscle mass.
Production
DHT is produced in the body when an enzyme called steroid 5-alpha reductase 2 interacts with the sex hormone testosterone. Males with a rare genetic condition called 5 alpha-reductase deficiency don't have the proper enzyme, and therefore produce little or no DHT.
Deficiency
According to the National Library of Medicine, people with DHT deficiency are genetically male, as they have the necessary Y chromosome. However, their sexual organs are usually malformed and may even appear female, a condition known as pseudohermaphrodism. In fact, the National Library of Medicine says many children with 5 alpha-reductase deficiency are raised as girls. In puberty, some secondary characteristics appear, including growth of the testes and the penis, if there is one. Men with this deficiency usually do not produce facial or body hair.
Reproduction
As DHT is important for normal testicular development, most men with no DHT cannot father children, according to the National Library of Medicine. "Most" does not mean all, however. In a study conducted in 1994, researchers at Cornell University looked at six men with 5 alpha-reductase deficiency. One already had a normal sperm count, and another produced a normal sperm count after a corrective procedure on the genitals. The rest were not capable of fathering children.
Consideration
Even if DHT deficiency doesn't severely affect a man's sex organs or limit his sperm count, it still may create an obstacle to fathering a child through normal sexual intercourse. That's because the Cornell researchers found that DHT also affects the production of semen, the bodily fluid that carries the sperm cells. DHT deficiency can reduce semen volume or make it more viscous--that is, thicker. In such cases, artificial insemination may be an option.
