Which of the following is NOT associated with Turner's syndrome?

Turner's syndrome is a chromosomal disorder characterized by the complete or partial absence of one of the two X chromosomes in females. Common features associated with this condition include primary amenorrhea, webbing of the neck, and short stature. Primary amenorrhea occurs because the ovaries are often underdeveloped, leading to insufficient estrogen production and the absence of menstruation. Webbing of the neck is a physical characteristic seen in many individuals with Turner's syndrome, resulting from lymphatic dysgenesis. Short stature is another hallmark of this condition, typically due to growth hormone deficiencies among other factors.

On the other hand, a port wine stain is not a recognized feature of Turner's syndrome. This vascular malformation usually appears as a discolored area of skin and is commonly associated with several other conditions, such as Sturge-Weber syndrome, but not with Turner's. Therefore, the correct answer indicates that port wine stains are not associated with Turner's syndrome, distinguishing it from the other features listed.