Medically reviewed by Vicky Davis, FNP
Written by Our Editorial Team
Last updated 3/24/2022
Although hair loss is usually associated with men, as a woman, it’s common to experience some degree of hair thinning throughout your life.
One of the most common signs of hair loss in women is thinning that develops around your part line. Over time, this can cause your hair’s natural parting to appear wider than normal and give your hair a less dense appearance with reduced coverage.
If you’ve noticed your part line widening in the mirror, there’s no need to panic. Like other forms of hair loss, the pattern hair loss that causes a widening part is treatable.
Below, we’ve covered the basics of hair loss in women, as well as how female pattern hair loss can affect your part line. We’ve also discussed several other forms of hair loss that may reduce your hair’s density and affect its appearance.
Finally, we’ve explained what you can do to treat a widening hair part, stop further hair loss and potentially regrow any hair that you’ve already lost.
A variety of health issues can affect your hair, but by far the most common is female pattern hair loss, or female androgenetic alopecia.
This type of hair loss is caused by the effects of androgen hormones, or male sex hormones, on your hair follicles.
Before we get into the specifics of pattern hair loss and its effects on your part line, it’s important to quickly go over the basics of what androgen hormones are and the effects that they can have on your body.
Androgens are hormones that are responsible for developing and maintaining masculine sex characteristics. They’re also responsible for contributing to the growth of muscle tissue. The most well-known androgen hormone is testosterone.
Although testosterone is typically viewed as a male hormone, both men and women produce testosterone and rely on it for certain biological functions.
For example, research has found that testosterone plays an important role in regulating your sex drive and response to sexual stimulation. It’s also linked to greater wellbeing and a lower risk of mental health issues such as depression and anxiety disorders.
Testosterone levels are much higher in men than in women. On average, men have between 300 and 1,000 nanograms of testosterone per deciliter of blood (ng/dL), while women usually have between 15ng/dL and 70 ng/dL.
So, what does testosterone have to do with your hair? Your body uses testosterone to create other hormones, one of which is called dihydrotestosterone (DHT).
As a woman, DHT doesn’t play a major role in your physical health. However, it can attach to receptors located throughout your scalp and, over time, cause your hair follicles to undergo a process called miniaturization.
This process shortens your hair’s anagen phase (the growth phase of your hair growth cycle), causing your hairs to become thinner and shorter. Eventually, hairs affected by DHT may no longer be able to penetrate through your scalp.
For men, this process usually begins around the hairline, before affecting the crown and other areas of the scalp.
Female hair loss, on the other hand, usually involves diffuse hair loss that first appears around your part line. This can gradually become more severe, resulting in noticeable hair loss and a wider part as a clear pattern of hair loss develops.
Over time, as hair follicle damage intensifies, a widening part line can develop into a “Christmas tree” pattern, with a wide part line at the front that narrows as it moves towards the back of your scalp.
Not everyone is equally at risk of developing a wide part line. Experts believe that genetics play a major role in this type of hair loss, with some women more sensitive to the effects of androgen hormones like DHT than others.
Certain biological factors may increase your risk of experiencing female pattern hair loss and a wide part line.
For example, women with polycystic ovary syndrome (PCOS) are more at risk of female pattern hair loss. It’s also common to develop this form of hair loss after menopause, potentially due to changes in hormone levels.
While most cases of a widening part are the result of female pattern hair loss, a variety of other factors can contribute to hair shedding around your part line. These include illnesses, nutritional deficiencies and even certain hairstyling techniques.
Other potential causes of a widening part line include:
Infections and illnesses. You may shed hair during or following an illness or infection, especially if it causes you to develop a fever. Diseases such as COVID-19 can cause telogen effluvium hair loss that may affect your part line or cause a thinner ponytail.
Trauma and shock. You may lose hair if you’ve recently been through a psychologically or physically traumatic experience. Some people also develop hair loss after undergoing major surgery.
Changes in hormone levels. Decreases in your levels of hormones, such as estrogen, can contribute to sudden hair loss. These hormonal changes can occur after giving birth, potentially causing temporary postpartum hair loss.
Iron deficiency. Hair loss is a common symptom of iron deficiency, a nutrient deficiency that may occur if your diet is low in iron or if you have a digestive health issue that stops your gastrointestinal tract from properly absorbing iron.
Crash dieting. Healthy hair growth depends on a healthful diet. Crash diets, particularly diets that restrict total calories or protein intake, may affect hair growth and contribute to diffuse thinning around your part line and other areas of your scalp.
Tension on your hair follicles. Hairstyles and devices that pull on your hair shafts, such as braids, cornrows, hair extensions and tight ponytails, can potentially cause a form of hair loss called traction alopecia, or ponytail hair loss.
Styling and hair care techniques. Some hair care techniques, such as brushing your hair excessively or using strong hold hair products, can damage your hair and cause a reduction in hair volume.
Medications. Hair shedding can occur as a side effect of certain medications, including retinoids, beta-blockers, anticoagulants, anticonvulsants and thyroid medications. It’s also common to shed hair after stopping medications that contain estrogen.
Medical treatments. Certain medical treatments, such as chemotherapy and radiation therapy for cancer, may cause you to temporarily shed hair. These treatments usually cause loss of hair on your scalp, face and body, not only around your part line.
Not all of these causes of hair loss are permanent. For example, telogen effluvium — which can be caused by stress, illnesses, trauma, nutritional deficiencies and some types of medication — usually involves excessive shedding that resolves once the causative issue is treated.
Our guide to the most common types of sudden hair loss goes into more detail about the factors that may cause you to lose hair around your part line or in other parts of your scalp.
Hair loss that causes your part line to widen is almost always treatable, usually with medication to prevent further hair loss and promote hair growth.
If your hair loss is caused by something other than androgenic alopecia, you may also be able to improve hair growth and add extra thickness by making some changes to your lifestyle and hair care habits.
The first step in treating a widening part line is identifying the cause. You can seek help for hair loss by talking to your primary care provider or with our personalized hair loss treatments.
If your healthcare provider thinks your hair loss might be caused by a hormonal issue, disease or nutritional deficiency, they may perform a scalp biopsy or order blood tests. These are used to identify or rule out issues such as iron deficiency anemia or thyroid disease.
Most of the time, female pattern hair loss can be diagnosed by looking at your hair loss pattern and general medical history.
Most of the time, female hair loss can be treated using minoxidil, an FDA-approved topical hair loss medication that’s available over the counter.
Minoxidil works by moving your hair follicles into an active hair growth phase. It also dilates the blood vessels in your scalp, which can increase blood circulation and may improve blood flow to your hair follicles.
Scientific research on minoxidil is positive. Most women who use it find that their hair loss either stops or slows down significantly after a few months of use, while others regrow lost hair.
These medications work by reducing the levels of hormones that damage your hair follicles and affect your hair cycle. Your healthcare provider may recommend taking them if minoxidil doesn’t fully treat your hair loss.
If you have advanced hair loss, or if you’d like fuller hair than what’s possible with minoxidil and other medications, you may want to consider hair transplantation surgery.
This type of procedure involves removing DHT-resistant hairs from the back of your scalp, then relocating them to increase the density of hair in your part line. Performed well, hair transplant surgery can produce natural-looking results and restore hair in areas with visible thinning.
Pricing for hair transplant surgery may vary based on your location and the severity of your hair thinning, with procedures typically ranging from $3,000 to $15,000 or more.
While a healthy lifestyle and good hair care habits are unlikely to reverse severe hair loss or an overly wide part, they can help to support hair growth and keep your hair looking and feeling its best. Try the following habits to keep your hair strong and healthy:
Eat a balanced, healthy diet that’s rich in vitamins, minerals and other nutrients.
Consider using hair health supplements, such as our Multivitamin Gummies.
Use a shampoo that’s formulated to stop shedding, such as our Triple Threat Shampoo.
Whenever possible, let your hair dry naturally after washing and conditioning.
When you blow-dry your hair, use the lowest heat setting to avoid damage.
Only brush or comb your hair when you need to, not on a daily basis.
When you brush your hair, do so gently and avoid pulling on the hair roots.
Consider changing your hairstyle to something that puts less pulling pressure on your hair follicles.
Avoid using hair straighteners, curling irons, hot combs or other products that apply heat directly to your hair shaft.
If you smoke, try to stop. Smoking can damage your hair’s DNA and contribute to hair loss.
Our guide to thickening your hair goes into more detail about the right habits and lifestyle changes that you can make to support healthy hair growth.
A widening hair part is a common sign of female pattern hair loss, and it’s important to treat it if you notice it when you style your hair or look in the mirror.
You can treat pattern hair loss and improve your hair density using proven, evidence-based hair loss treatments for women such as minoxidil and, if necessary, anti-androgen medications such as spironolactone.
These medications work by stimulating growth and preventing follicular damage. Used regularly, they can produce real, visible improvements in your hair in just a few months.
Interested in learning more about combating hair loss? Our 101 guide to female hair loss covers everything you need to know about the causes of hair loss in women, as well as your options for preventing thinning and maintaining a thick head of hair at any age.