A case study presented in the Hong Kong Medical Journal highlights a 66-year-old citizen of China who has lived his entire life as a man, only to find out he was actually a woman. Doctors made the discovery after a swollen abdomen he was visiting the hospital for turned out to be a benign ovarian cyst.

Orphaned as a child, the patient told doctors he had stopped physically maturing right after puberty at 10 years old, Channel NewsAsia reported. Currently four-and-a-half feet tall, with no testicles and a history of urinary leakage, doctors said the man's condition is similar to only six other medical cases on record.

The Vietnam-born hospital patient ultimately learned his physical condition was the result of two rare genetic disorders: Turner syndrome and congenital adrenal hyperplasia.

Turner syndrome usually occurs when sex chromosomes fail to separate during the formation of an egg or sperm. This confusion results in a missing or incomplete X chromosome, of which women are supposed to have two.

According to the Turner Syndrome Society of the United States, around 71,000 women in the U.S. are currently living with Turner syndrome. Women are diagnosed using a karyotype blood test, which tracks an individual's chromosome makeup.

Congenital adrenal hyperplasia is a genetic disorder that blocks the adrenal gland's production of hormones such as cortisol and androgen. This lack of hormone production can lead to abnormal development in both male and female genitalia.

The National Institutes of Health estimates that around one in 16,000 births are affected by congenital adrenal hyperplasia.

In the case study, researchers indicated that the patient will continue "perceiving himself as having a male gender with the possible need of testosterone replacement."