What is the purpose of pubic hair?

It is there to prevent yeast and bacterial infections of the vagina and urethra, and also to help keep the area moist to prevent micro-tears during sex. It also helps to hold in the scent of pheremones to arouse men.
 You are asking the age-old question, “why do we have hair down there?” There are many theories behind why humans have pubic hair. One thought is that the hair that grows around the genitals and under the arms lock in sexually stimulating scents called pheromones. For some, scents released from these areas are noticeable and can increase sexual desire. For others, pheromones might not be obvious but may be subliminally sensed. Some people believe that pubic hair keeps our genitals warm. Others believe that the purpose of pubic hair is to prevent dirt from entering the vagina. (The Sexpert does not have an exact answer on the purpose of pubic hair and its effect on the sexual experience because it is not completely known. The exact evolutionary explanation to why we have pubic hair is similar to wondering why we have eyebrows…or why some people only have one…) With or without purpose, pubic hair can be ornamental and eye-catching to its owner or to others. How you style your pubic hair is up to you. There are women and men who prefer one look over others (just as some prefer a mohawk, mullet or total shave for the hairdos on their head) and there are people who don't think twice about how their pubic hair looks. Pubic hair is unique in amount, color and consistency. Some women let their pubic hair grow into a full coverage of the pubic area while others prefer to keep their hair trimmed. (some seasonally prefer to have a neatly shaven “bikini line”). There are also women who choose to remove some or all of the their pubic hair. Shaving, waxing or removing your pubic hair is by no means permanent. As the hair starts to grow back, however, it can be very itchy and uncomfortable.