Hair normally grows at a rate of a half inch per month, and each hair has a growth phase for about four to six years. Following this, the hair usually falls out. In most people, this is no big deal as another hair follicle simply grows back in its place. Sometimes however, the hair does not grow back and the follicle closes itself up. This is a condition medically known as androgenic alopecia. Alopecia sometimes occurs in women, however it is usually caused by excessive testosterone and thus is a male disorder. The difference is in the appearance. Male pattern baldness will appear in a spot or around the crown on the head, where as women tend to lose their hair from the entire head. Having this disease in a woman means that the hair loss could occur at any age. Disease is anther factor of hair loss for women. Autoimmune disorder can cause hair loss in large clumps or patches. Anemia, chronic illness or thyroid disease can cause loss as well.