What is hereditary hair loss in women?
Hereditary pattern hair loss, or androgenetic alopecia, is a common type of hair loss. There is a distinctive pattern of hair loss, and in women it is sometimes also referred to as female pattern hair loss, female pattern baldness, or female pattern alopecia.
This type of hair loss occurs in a person when changes in certain hormones affect the hair follicles on their scalp. There is a hair growth cycle in which hairs have an active growing phase (the anagen phase) and a resting phase (the telogen phase). In a process referred to as miniaturisation, the affected follicles shrink, getting progressively smaller with each new hair growth cycle, and the hairs they grow are lighter and gradually are shorter in length with an increasingly smaller diameter until the follicles can no longer grow hair.
Eventually the number of hairs in the resting phase increases while those in the active growing phase decrease, and the period between the shedding and growing phases becomes longer. When hairs are in the resting phase, they can shed more easily because they are not as firmly anchored to the scalp as those in the active growing phase. Over time, there are a decreased number of hairs on the head.
What are the symptoms of female pattern hair loss?
The decreased number of hairs will make the scalp become more obvious. There will be a distinctive pattern to the hair loss, but it differs between men and women. While hair loss in men tends to be at the front and sides of the scalp that progresses to the back (receding hairline), and also affects the crown, in women the hair loss occurs at the top of the head. In addition the pattern of the hair loss in women is more diffuse and less noticeable than in men. A woman's parting may appear wider. If it is affected at all, the hairline above the woman's face usually shows only slight signs of thinning.
It's not possible to predict the rate of hair loss, but it generally progresses gradually. Only on rare occasions does a woman with this condition become completely bald.
What causes female pattern hair loss?
Hereditary pattern hair loss occurs in people who have a family history of this type of hair loss and the inherited genes - it is thought that more than one gene plays a role - can come from either one, or both, parents. It is possible that early-onset female pattern hair loss - when hair loss begins earlier than normal - could have a different genetic cause than late-onset female pattern hair loss.
Androgens, a group of hormones linked to male traits, are present in both men and women, and they are thought to be responsible for the changes to the hair follicles in this type of hair loss, though the link in women is less clear. Most women with hereditary pattern hair loss have no medical indication of higher levels of androgens, but it is possible that scalp sensitivity to these hormones could play a part in the condition.
In some women female pattern hair loss could be an indication of polycystic ovary syndrome (PCOS) - a condition that affects the ovaries.