Hair loss is much more common in women than one would imagine.

Women generally have a diffuse thinning (less hair all over), in contrast to men who more frequently have a "patterned" type. Women often maintain their frontal hairline, with their hair loss quite gradual, but accelerating during pregnancy and at menopause. It is more often cyclical than in men, with seasonal changes that reverse themselves, and it is more easily affected by hormonal changes, medical conditions, and external factors.

The hair loss in women may be divided into three categories:

Localized Hair Loss
This pattern of hair loss is subdivided into scarring and nonscarring types. Examples of the nonscarring variety include hair loss following long-standing pulling of the hair (traction alopecia), hair loss in association with surgeries such as facelifts and certain other autoimmune conditions such as alopecia areata. Scarring alopecia can be caused by a variety of medical or dermatologic conditions such as lupus and lichen planus, or local radiation therapy.

Patterned Hair Loss
Women with this type of hair loss have a pattern similar to what we observe in men. They have thinning in front or on top of their scalp, with little hair loss in the permanent zone around the sides and the back. Women with patterned hair loss may be excellent candidates for surgical hair restoration.

Diffuse Hair Loss
This type of hair loss involves a generalized thinning that affects all parts of the scalp. It is the most common pattern of hair loss in women, and involves loss of hair and a diminishing in the thickness of the hair shaft. It is generally termed diffuse un-patterned Alopecia. However, there are numerous medical conditions that can cause diffuse hair loss such as the use of certain medications, anemia, thyroid disease, hormonal conditions and the present or recent occurrence of significant stressors.