Anagen – the active growth period
Catagen – short recession period
Telogen – resting period.
Hair that reaches the end of its life is shed and healthy new hair grows in its place.
Within this growth cycle, daily loss of about 100 hairs is considered normal.
Causes of Hair Loss in Women
In women age-related hair loss usually occurs only after menopause. The production of female sex hormones is reduced and the hair follicle-damaging effect of dihydrotestosterone may come to the fore. Therefore, women can be affected also by hormonal hair loss as men after menopause. The previously healthy hair looks thin and lifeless.
More severe hair loss can result in female pattern baldness where there is a family history of female pattern baldness as well as some of the above mentioned causes. The reason for female pattern baldness is not fully understand. In women the hair thins usually along the crest.
Diffuse hair loss
The different causes of diffuse hair loss
A hair loss of up to 100 hairs a day is considered normal. If the hair loss exceed this figure, there may be different causes – for example, pregnancy, taking certain medications and a poor diet.
Hair loss during pregnancy and after birth
Women often lose hair in the two to three months after childbirth (postpartum effluvium): This is because, during pregnancy, estrogen levels in the blood are very high. With the birth of a child this will drop sharply and may result in hair loss as the hair grows from the growth stage to the resting stage. Once the hormone levels return to normal, the hair loss should stop. Normally the pregnancy-related diffuse hair loss ends six months after the birth of a child.
Circular hair loss (alopecia areata)
When circular hair loss (alopecia areata) occurs – usually temporary – the loss of hair in a limited, usually circular or oval area with a diameter of two to 2.5 centimetres. Alopecia areata can occur regardless of age or gender. The cause of alopecia areata is unknown. Doctors may recommend taking measures to help strengthen the immune system and reduce stress factors. Once the body immunity has recovered, and the hair will grow back.
Hair loss caused by the misapplication of cosmetic products
Many cosmetic products contain synthetic substances which may cause irritation or allergic reactions of the scalp. The misapplication of such products may disturb the balance of the scalp and may result in hair loss.
Hair loss due to taking medication
Some medications – for example, blood coagulation preparations, antidepressants, antihypertensive, the birth control pill or high doses of vitamin A – can damage the hair roots and lead to diffuse hair loss, especially with long-term use.
Hair loss due to unbalanced and inadequate nutrition
Iron, zinc, sulphur and vitamins of the B group care for healthy hair. People who do not have a balanced diet may experience hair loss.