What Causes Hair Loss in Women? Especially at an Early Age Like in Their 20s?

Is there anything that can be done to fix it?

Doctor Answers 5

Hair loss in young women

  • There are two main causes of hair loss in a female in her 20s:
  1. Genetic hair loss. About 10% of women start to develop hair loss in their 20s. The key feature is worsening hair loss in the centre of the scalp and progressive "miniaturization" of hairs. 
  2. Telogen effluvium (hair shedding). About 30 % of women under 30 have low iron. This can sometimes cause hair loss 
Other causes of hair loss are possible to - so if you are worried see a dermatologist. Low thyroid levels, hairstyles, excessive heat, illnesses, dieting, high stress can all give hair loss.

At minimum, most would recommend a few simple blood tests and a detailed scalp examination.  

Hair Loss in Young Women

Women in their 20s can experience hair loss. For some women its genetic, its iron deficiency, its diet, or injury, or medication. There are several reasons why you could be experiencing hair loss at such a young age; it's definitely recommended that you visit your doctor for an examination. 

Robert Jones, MD
Mississauga Hair Restoration Surgeon
5.0 out of 5 stars 12 reviews

Female Hair Loss

Androgenetic alopecia (aka androgen-related hair loss or female-pattern hair loss or hereditary hair thinning) is the most common cause of hair loss in women. However, there are numerous other important, and common causes, of hair loss that must be investigated in women. A proper history and physical exam will help determine the diagnosis for hair loss. A thorough review of a patient’s medical history (including medications, allergies, family history, and diet) is of utmost importance in identifying the cause of hair loss. A history of menses, pregnancy, and menopause is assessed. Specific hair-related questions that might be asked include: 

-When did the hair loss start?

-Was the hair loss sudden in onset or gradual? If hair loss is sudden, there is likely a disruption of the hair cycle (telogen effluvium) whereas chronic (longstanding) hair loss may indicate an abnormality of the hair follicle (androgenetic alopecia).

-Where have you noticed the most hair loss? When a patient presents for evaluation of hair loss, she may be referring to a single patch of alopecia (alopecia areata) or to extensive hair breakage from use of hair products (hair shaft damage). Patterned hair loss is seen most commonly in androgenetic alopecia

-What is your normal hair care routine? Hair care practices and use of hair cosmetics (i.e. bleaching, permanent waving) can be key factors in determining the cause of hair loss.

A detailed examination of the hair and scalp is performed with good lighting and magnification. Hair distribution over the rest of the body is also assessed to see if there is too little or too much hair in other areas.  

Certain labs can be quite helpful for determining the cause of female hair loss. Screening for thyroid abnormalities, low iron levels and anemia are important during a female hair loss evaluation. An iron panel and complete blood panel (CBC) are useful labs to obtain for women with heavy or long-lasting menses. 

For women with androgenetic alopecia, extensive hormonal evaluation (such as measuring testosterone levels) is usually NOT needed unless any of the following conditions are present: irregular menses, infertility, hirsutism (excess body hair), severe acne, or galactorrhea.

In general, 4 labs that I routinely order in women with hair loss include: CBC, thyroid panel, Ferritin (to measure iron levels), and Vitamin D (which is essential for proper hair growth).

Scalp biopsies can be used to make or confirm a diagnosis of alopecia and can be essential in guiding therapy. 


1. Androgenetic Alopecia (AGA), or hereditary hair thinning, is the most common form of hair loss in humans. This condition is also known as male-pattern hair loss or as female-pattern hair thinning. Onset may occur in either sex at any time after puberty and the majority of thinning occurs in the teens, 20s, and 30s. 

2. The second most common cause of female hair loss is thyroid disease (either hypothyroidism or hyperthyroidism). Other common causes of hair loss include inadequate dietary protein, or low levels of vitamin D or iron. 

3. Categories of drugs that may cause hair loss include: anticancer drugs, anticoagulant drugs, anticonvulsant drugs, beta blockers, tricyclic antidepressants, and oral contraceptives. Discontinuation of the medication is usually followed by hair regrowth. Oral contraceptives (birth control) must be selected carefully to avoid progestins with an androgenic effect. 

4. Telogen Effluvium may cause sudden hair shedding. Common causes of Telogen Effluvium include high fever, childbirth, severe infections, severe chronic illness, major surgery, thyroid disorder, crash diets, inadequate protein, and certain drugs. The shedding often starts months after the inciting cause but is always self-limited and reversible if the offending cause is corrected or resolved. 

5. Damage to the hair shaft by improper cosmetic techniques can cause hair breakage. There is little damage from normal dyeing, bleaching, waving or straightening. However, breakage can occur with too much tension during waving; waving solutions left on too long; or improperly neutralized, waving, and bleaching on the same day or too frequently. Other causes of hair breakage include excess tension in braids, ponytails, or cornrows.

6. Alopecia Areata is an autoimmune disease that affects almost 2% of the population in the United States. Inflammatory cells target the hair follicle, thus preventing hair growth. Typically a small round patch of hair is noticed; this patchy hair loss may regrow spontaneously. In other cases there can be extensive patchy hair loss, and in rare cases, there is loss of all scalp and body hair (Alopecia Areata Universalis).

In summary, there are multiple causes for hair loss in women. In order to determine the exact cause of hair loss, a complete review of the patient’s medical history, detailed hair and scalp exam, and laboratory test(s) are necessary. Appropriate treatment and counseling can then be tailored to each patient’s needs. 

Sahar Nadimi, MD
Chicago Facial Plastic Surgeon
5.0 out of 5 stars 1 review

What Causes Hair Loss in Women? Especially at an Early Age Like in Their 20s?

Thank you for your question.

Loss of hair is a natural process when it is between the limits that the body can restore them. When the capacity of the body to restore the hair loss is beaten by the excessive hair loss then we can name this situation something that should be treated. Women started to experience balding even more in the last 2 decades. It is getting more and more common also in women population. However it is also good to know that this problem is also treatable when it is present in women.

To obtain alive hair follicles implanted in higher rates, the latest technique being used is not the only manner, it is also affected by compliance of implantation area that we found a better way to improve as a result of our researches, The Organic Hair Transplantation. By this new and unique Organic Hair Transplantation Technique, before the extraction and implantation processes; we regenerate the implantation area with injection of stem cell enriched fat tissue. Regeneration of cells in target area before FUE transplantation with the support of stromal stem cells results in higher rate of alive thicker hair follicles.

Bulent Cihantimur, MD
Turkey Plastic Surgeon
4.9 out of 5 stars 79 reviews

Hair loss

First, go get a blood test:   CBC, CMP, TSH, T4, ferritin. Anemia , iron deficiency, and hypothyroidism are common causes of hair loss that can be treated fairly easily.   If they are within normal limits, then start to look at stress level,  endurance exercises, and hormones can be an issue.

Erik Suh, MD
Bellevue Family Physician
5.0 out of 5 stars 5 reviews

These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.