Hereditary hair loss

Also known as alopecia

While men experience "male pattern baldness" (vertex balding and/or receding frontal hairline), women generally experience female pattern baldness, which is a thinning over the top of the head or crown while maintaining a frontal hairline.

Key points:

  1. Hereditary hair loss is most common in men but also occurs in women; for every five men with the condition, three women are also affected.
  2. For normal hereditary hair loss there is no cure as such but treatment may help slow or halt the hair loss.
  3. Early treatment works the best, to prevent further loss.


Hair cycle of growth and rest

Like your skin and nails, your hair goes through a finely tuned cycle of growth and rest. Excessive hair loss can occur at any time this delicate cycle is upset.

  • About 90% of a person's scalp hair is continually growing, a phase that lasts between two and five years. Scalp hair grows about 1-2cm per month.
  • The remaining 10% of the scalp hair is in a resting phase that lasts between two and three months.
  • At the end of its resting stage, the hair goes through a shedding phase, which normally results in the growth of a new hair.
  • When a hair is shed, it is replaced by a new hair from the same hair follicle located just beneath the skin surface.

Regrowth can slow with ageing

Most people lose between 50 and 100 strands of hair every day. As hairs fall out naturally, new hairs grow back. However, with age this natural regrowth process may slow or stop, causing thinning and/or baldness to occur. If you are concerned, see your doctor for an evaluation to find out if your hair loss is normal or if it is due to an underlying medical problem.

What is hereditary hair loss?

Hair loss that 'runs in families' is called hereditary hair loss. It is also known as androgenic alopecia. Your risk of hereditary hair loss increases if you have relatives who have experienced hair loss. Your genetic blueprint for hair loss will affect things like:

  • how old you are when hair loss begins
  • how fast you lose hair
  • the pattern and extent of your hair loss/ baldness.

The hair cycle changes in those with hereditary hair loss:

  • the hair follicles become smaller
  • the growth phase is shorter
  • hairs are shed faster.

Consequently, hair becomes shorter, thinner and even colourless.

Male hereditary hair loss

The most common type of hair loss starts in males from about the age of 30, but could occur at any age past puberty.

  • It is known as male pattern baldness.
  • It is thought to be hereditary and is also dependent on the extent to which the male hormone testosterone is converted in the scalp to another hormone, dihydroxytestosterone.
  • Hereditary hair loss accounts for 99% of hair loss in men.

How quickly or slowly baldness develops, and the pattern of hair loss, appear to be genetically determined. Although this type of baldness can also affect women, the pattern of baldness is different in males and females.

Female hereditary hair loss

Hair loss is not something that happens to women only after the menopause.

  • It is also known as female pattern baldness.
  • The typical pattern is thinning over the top of the head or crown while maintaining a frontal hairline.
  • It usually begins about the age of 30, becomes noticeable around age 40, and may be even more noticeable after menopause.
  • By the age of 50 almost half of women will experience some degree of hair thinning.


Pattern of hair loss - hereditary

  • Male. In males, baldness usually begins with progressive thinning at the hairline, followed by the appearance of a thinned or bald spot on the crown of the head.
  • Female. Women with hereditary baldness rarely develop bald patches. Instead, they experience a general thinning of their hair.

Other forms of hair loss

Hair loss that is not hereditary may be caused by:

  • pregnancy
  • hormonal or other medicines
  • severe nutritional deficiencies
  • chemotherapy
  • autoimmune disorders
  • an underactive or overactive thyroid gland
  • scalp trauma, including reactions to hair care products and hair grooming methods.

Also see: Temporary hair loss

When should you seek medical advice?

You should seek medical advice for hair loss if:

  • hair loss is sudden or distressing
  • you have been diagnosed with an autoimmune disorder such as systemic lupus erythematosis, nutritional deficiency or thyroid disease
  • you have been recently treated with chemotherapy or have used a new medication (including hormonal medications), or
  • the hair loss cannot be explained by hereditary factors.


To lose your hair slowly is a normal part of the ageing process for most men and some women. Treatment is not usually necessary. However, hair loss that occurs rapidly or early in life can be distressing. If you wish to slow hair loss, there are treatments are available. Early treatment works the best to prevent further loss.

If hair loss is caused by a temporary situation such as illness, medication, stress or insufficient iron, however, the hair loss will stop when the cause is resolved.

Medications for hereditary hair loss

Treating hereditary hair loss with medications is more successful when started early, at the first signs of hair thinning. Treatment must be continuous to maintain hair regrowth. If the treatment is stopped, regrowth ceases and hair loss will start again. The effectiveness of treatment may not be measurable for up to 12 months.

  • Ask about side effects before use. Hair loss medications have a small risk of causing side effects, and you should make sure your doctor or pharmacist explains to you what these are before starting treatment.
  • Effectiveness. The results differ from person to person, but on average three out of five who use these medications find hair loss is slowed or stopped - and some may even get increased hair growth.

Finasteride (Propecia)

This is a prescription only treatment for hereditary hair loss in men (male pattern baldness). It works by blocking the conversion of testosterone to dihydrotestosterone. The hair follicles are then not affected by this hormone and can enlarge back to normal.


  • Some hair regrowth occurs in about 2 in 3 men who take a finasteride tablet each day.
  • In about 1 in 3 men there is no hair regrowth but most do not have any further hair loss whilst taking finasteride.
  • It has no effect in about 1 in 100 men.

Points to note about finasteride:

  • It takes about 4 months for any effect to be noticed and up to 1-2 years for full hair growth.
  • Hair loss returns if treatment is stopped. Therefore, if successful, you need to carry on treatment to maintain the effect.
  • Side-effects are uncommon. The most common is that about 2 in 100 treated men report a loss of sex drive (libido).

Minoxidil topical lotion (Regaine, Headway)

Is a rub-on treatment that can be bought from your pharmacy. It can be used by both men and women. It needs to be applied twice daily to the scalp while it is dry.

  • It usually works best for hair loss at the top and back of the scalp, where there is still some remaining hair.
  • You should not use more than the recommended dose, as overuse will not achieve better or faster growth.
  • It can slow progressive balding in hereditary hair loss, but not all hair will grow back.
  • It usually takes about 4 months or more for any effect to be noticed.
  • Hair loss will resume if treatment is stopped.
  • The most common side effect is an itchy scalp.

Precautions with lotion use

  • You should always wash your hands thoroughly after applying the lotion, and avoid getting it in your eyes, nose or mouth.
  • When taken in tablet form, minoxidil is used to treat high blood pressure and, if accidentally swallowed, could potentially affect normal heart function and blood pressure.
  • This product should not be used by women during pregnancy or breastfeeding.

Hair transplantation

Hairstyles can often be effective in hiding thinning hair.

  • Men: In some men, hair transplants can redistribute the remaining hair.
  • Women: Hair transplantation is often less satisfactory in women than in men. Partial hair pieces or wigs are recommended for women if the hair loss is severe.

Surgical hair replacement can give you back a head of your own hair. Available since the 1950s, surgical hair replacement is a low-risk procedure.

  • Tiny plugs (grafts) of your hair-bearing skin are surgically removed and transplanted into tiny holes made in the scalp where your hair is thinning.
  • These plugs are removed from the band of hair extending from above your ears and around the back of your scalp.
  • During one hair transplant session, up to 60 or 100 hair plugs are transplanted.
  • Local anaesthesia and mild sedation minimise discomfort during surgery. Hospitalisation usually is unnecessary.
  • A few days after the operation, tiny scabs form around each hair graft.
  • When the scabs disappear, the transplanted hairs usually fall out.
  • New hairs generally start to grow within a few months.

Several appointments may be needed

If the baldness and thinning is extensive, one should not expect to walk out of the first surgery with a full, natural-looking head of hair. Even after the transplanted hairs begin growing, these widely scattered clumps may look conspicuous. Additional surgical appointments may be needed to fill the bald spaces. Typically, it takes three or four sessions to cover a bald area. It may take a year or two before you will be pleased with your new appearance.


Hereditary hair loss is part of your genetic blueprint. While there isn't anything you can do to change your genes, there are a few things you can do that may help keep your hair healthy and strong for longer.

Dietary protein is important

Hair is made up of a form of protein, the same one found in fingernails and toenails. Everyone, regardless of age, should eat an adequate amount of protein to maintain normal hair production. Protein is found in meat, chicken, fish, eggs, some cheese, dried beans, tofu, grains and nuts.

Be gentle with your hair

  • Avoid tight hairstyles, such as braids, buns or ponytails.
  • Avoid twisting, rubbing or pulling your hair.
  • Avoid hair lotions that are heavily perfumed.
  • Avoid excessive heat treatments.

Self care

Hereditary hair loss is a normal part of the ageing process. However, when baldness occurs suddenly or early in life it can be distressing. Hair loss is particularly upsetting for women. Talking with others who have experienced hair loss may help.

NZ Alopecia Facebook support group
NZ Alopecia NZ website Information from fellow New Zealanders living with alopecia. Links to support groups, personal experiences through to information about wig subsidy for those who have experienced "serious hair loss because of a medical condition or from certain cancer therapies."

Credits: Health Navigator Team.