Causes of Hair Loss in Women

The causes of hair loss in women are often a surprise to the person suffering the loss. That's because hair loss and hair thinning is emotionally challenging, there is a sense of urgency and they are often looking at their scalp or hair care products when the problem may be much more complex. 

The good news is many causes of hair loss are reversible once you figure out why your hair is thinning. 

How does a dermatologist evaluate hair loss?

In my dermatology practice I see many female patients whose hair is thinning. The first thing I do is examine their scalp.

• If there are lesions and physical changes on the scalp, then we look for the cause. Conditions such as fungal infection, lupus, lichen planopilaris, frontal fibrosing alopecia, alopecia areata etc. are examples of specific focal causes of hair loss. The evaluation and treatment process are specific to the condition.
• If the scalp is normal then we have the challenge of figuring out what is turning down hair production. Typically, it is something internal and the hair loss or thinning is general. Many of the causes of generalized scalp hair loss are reversible.

It's important to know that this information applies to both men and women.

What are the most common causes of hair thinning and hair loss in women when the scalp skin appears normal?

Genetic female patterned baldness

Also called androgenetic alopecia. (In men it is called male patterned baldness.) In women, the hair loss of genetic female patterned baldness is typically worse over the crown of the scalp than it is in the frontal hairline running on the top of the forehead. Women at the greatest risk are those with a family history of balding in either female or male relatives.

Hair loss from medicines

Many commonly used medicines cause hair thinning. Some of the more common families of drugs that cause hair loss include some antidepressants, beta blockers (used for blood pressure management), cholesterol-lowering drugs, hormones, anti-inflammatory drugs (used to treat pain), and stomach-acid-inhibiting drugs. A good dermatologist can evaluate your list of medicines to determine if you are on a medicine that might be contributing to hair loss.

Telogen effluvium

This condition occurs when your body is under such great stress that it starts to shut down optional processes, such as hair growth. It’s a survival mechanism to help ensure that vital resources are not squandered during times of grave physical stress.

When the body feels the danger has passed, it starts making hair again. This typically takes a few months after the stress has ended. But, as the new hairs grow, your follicles drop old hairs in what can be a massive shedding. Basically, the new hairs push the old ones out of the follicles. This is associated with an alarming, and often dramatic, hair thinning. It takes a month for the new hair to reach the surface of the follicle. It takes even longer for it to make a visible difference to a thin scalp.

The good news about telogen effluvium is that in a month, new short hair “sprouts” will visibly emerge from the follicles. You will see them as a crop of little hairs all about the same length across your entire scalp. This signals that the process is resolving and thicker hair is on the way. - Dermatologist Dr. Cynthia Bailey

Examples of the type of events that can cause telogen effluvium include:

• having a baby,
• undergoing a surgical procedure,
• developing a serious illness (such as pneumonia),
• experiencing radical changes in weight (especially weight loss), and
• being under severe emotional stress like being in a car accident or suffering the death of a loved one.

Know that there are many other physiologically traumatic events that will trigger telogen effluvium. 

Hair loss caused from internal medical conditions.

The most common causes I see are thyroid problems and anemia. There are also other vaguer medical conditions such as underlying blood cancers like leukemia, complex endocrine problems, etc.

When I am evaluating a woman for hair loss and the explanation does not seem to be one of the first three causes, and her thyroid tests and blood count are normal, then I recommend that she be evaluated by her primary care physician. I want her to have a complete physical examination and lab tests aimed at detecting one of the underlying internal disease associated with hair loss. 

I have many patient stories where this evaluation turned out to be lifesaving; unexplained hair loss was the first symptom, and because we were tenacious about getting them evaluated for internal problems, they were diagnosed with something early and treated successfully. It's a 'squeaky wheel getting the grease' analogy. In my opinion, it pays to be squeaky when it comes to your health. Diffuse hair loss can be a barometer of that.

What can you do if you and your dermatologist have not been able to find a specific cause for your hair loss or hair thinning?

These are the general recommendations that I give to my patients.  The concept applies to both men and women.

3 Tips to Stop Hair Thinning or Hair Loss in Women

Stop any medicines that can contribute to hair loss.

Ask your dermatologist to do a search of all your medicines to see if alopecia is associated with them. If the medicines are prescription, this needs to be coordinated with your prescribing doctor’s supervision.

Stabilize your hormones.

Going on and off hormones (including birth control pills, menopause hormone supplementation, and thyroid medicines) will throw you in and out of bouts of telogen effluvium and/or medication-induced hair loss. This may go on until your hormone levels are stable.

Make it a priority to stabilize your weight, health, and emotional well-being.

Again, telogen effluvium will be triggered by significant swings in your physical condition and it is possible to have repeated episodes of telogen effluvium that sort of blur together and add up to very significant thinning. I would add to this the recommendation to consistently get a good night’s rest, eat a health promoting well-balanced diet, get regular exercise, and engage in healthy stress relieving activities like spending time in nature. Sometimes we think we are doing fine but our physiology, and hair follicles, think otherwise. 

Author: Dr. Cynthia Bailey M.D. is a Board Certified dermatologist practicing dermatology since 1987. She has done well over 200,000 skin exams during her career and authors the longest running physician written skin health blog in the world.