Turning 40 can be a good time to pay closer attention to the health numbers you can't see or feel.
Changes in hormones, metabolism, cholesterol, blood sugar, thyroid function, bone health and nutritional status can occur as we get older—sometimes without obvious symptoms.
Blood testing can provide useful information about what's happening inside your body and may identify results worth discussing with your healthcare provider.
That doesn't mean every woman over 40 needs every test on this list. Your medical history, family history, medications, menstrual history, symptoms and individual risk factors all matter.
Here are seven blood tests women over 40 should know about.
1. Complete Blood Count (CBC)
A Complete Blood Count, commonly called a CBC, is one of the most frequently performed blood tests.
It measures several components of your blood, including:
Red blood cells
White blood cells
Hemoglobin
Hematocrit
Platelets
A CBC can provide useful information when evaluating anemia, infections and certain blood abnormalities.
For women who still menstruate, blood loss can also be relevant when investigating iron deficiency or anemia—particularly when periods are heavy.
If unexplained tiredness is one of the reasons you're considering blood work, read our guide Feeling Tired All the Time? 7 Blood Tests That May Help You Find Out Why.
→ Explore CBC and general health blood tests
2. Iron and Ferritin
Iron is essential for producing hemoglobin, which allows red blood cells to carry oxygen around the body.
Ferritin is a protein that stores iron and can provide information about your body's iron stores.
Iron-related testing may include:
Ferritin
Serum iron
Total iron-binding capacity (TIBC)
Transferrin saturation
Complete Blood Count
Women who experience heavy menstrual bleeding may be at increased risk of iron deficiency.
Possible symptoms associated with iron deficiency can include fatigue, weakness and reduced exercise tolerance, although these symptoms can have many other causes.
It's also important not to assume that tiredness automatically means you need an iron supplement. Testing can help establish whether iron status may actually be relevant.
→ Compare anemia, iron and ferritin tests
3. Thyroid Testing
Your thyroid is a relatively small gland with a large influence on processes throughout your body.
A common starting point for thyroid testing is thyroid-stimulating hormone (TSH).
Depending on the circumstances and initial results, additional measurements such as Free T4 may also be considered.
Symptoms associated with thyroid disorders can include:
Fatigue
Changes in weight
Feeling unusually cold or hot
Changes in heart rate
Changes in menstrual periods
Difficulty concentrating
The problem is that many of these symptoms can have other explanations.
That's why symptoms alone can't tell you whether you have a thyroid condition.
4. Cholesterol and Lipid Panel
Cholesterol becomes increasingly important to keep an eye on as we get older.
A standard lipid panel commonly measures:
Total cholesterol
LDL cholesterol
HDL cholesterol
Triglycerides
These numbers can contribute to an assessment of cardiovascular risk alongside factors such as blood pressure, smoking, diabetes, age and family history.
Importantly, high cholesterol often doesn't produce noticeable symptoms.
If you've already received an elevated cholesterol result, read our Top 10 Tips to Manage High Cholesterol.
→ Explore cholesterol and cardiac health tests
5. Blood Glucose and Hemoglobin A1c
Blood glucose testing measures the amount of glucose circulating in your blood at the time of testing.
Hemoglobin A1c (HbA1c) provides different information. It reflects your average blood glucose over approximately the previous two to three months.
A1c is commonly used when screening for or monitoring prediabetes and diabetes.
Risk can be influenced by several factors, including:
Age
Weight
Family history
Physical activity
Previous gestational diabetes
Blood pressure
Previous glucose results
You don't necessarily feel different when blood glucose first begins moving outside desirable ranges.
→ Compare diabetes and blood glucose tests
6. Vitamin D
Vitamin D plays an important role in bone health and several other processes in the body.
Your body can produce vitamin D following exposure of the skin to sunlight, while vitamin D can also come from certain foods and supplements.
A blood test called 25-hydroxy vitamin D is commonly used to assess vitamin D status.
Vitamin D can become particularly interesting to women as they approach menopause and later life because maintaining bone health becomes increasingly important.
However, fatigue or aches don't automatically mean someone is vitamin D deficient. Testing is the appropriate way to determine your level.
For more information about vitamin D testing, you can also read the USLabTesting guide 1,25 Vitamin D Test: Introduction and Information.
→ Explore vitamin and nutritional blood tests
7. Hormone Testing
Hormones can become a particular area of interest for women in their 40s because this is when some women begin experiencing changes associated with perimenopause.
Possible changes can include:
Irregular periods
Hot flashes
Night sweats
Sleep problems
Mood changes
Changes in libido
Laboratory testing may sometimes include hormones such as:
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)
Estradiol
Progesterone
Testosterone
However, hormone levels can fluctuate significantly, particularly during perimenopause.
That means a single result doesn't necessarily provide a complete picture, and menopause isn't diagnosed simply by ordering the largest possible hormone panel.
If you're approaching menopause or experiencing symptoms, read our existing guide Menopause: Treatments, Supplements, and Laboratory Testing.
What About Kidney and Liver Function?
Kidney and liver measurements are also commonly included in broader health blood work.
A Comprehensive Metabolic Panel (CMP) can provide information related to several areas, including:
Kidney function
Liver function
Blood glucose
Electrolytes
Calcium
Blood proteins
Kidney-related measurements can include creatinine and estimated glomerular filtration rate (eGFR).
If you'd like to understand creatinine in more detail, read Understanding Creatinine: What It Is and Its Importance.
You can also read Signs of Kidney Disease: Recognizing the Early Warning Signs.
→ Explore kidney and liver testing
Can You Test Several Things at Once?
Yes.
If you're interested in several health markers, ordering a broader health panel may be more convenient than purchasing each test individually.
For example, the USLabTesting Standard Health Panel combines:
Complete Blood Count (CBC)
Comprehensive Metabolic Panel (CMP)
Urinalysis
Lipid Panel
Thyroid-Stimulating Hormone (TSH)
That covers several of the health markers discussed in this article in a single panel.
→ View the Standard Health Panel
You can also compare other general health and wellness testing options.
→ Compare General Health & Wellness Tests
What About Blood Tests During Perimenopause?
Perimenopause can begin years before a woman's final menstrual period.
During this transition, hormone production can fluctuate considerably.
Some women experience noticeable symptoms, while others experience relatively few.
If you're experiencing changes such as irregular periods, hot flashes, night sweats or sleep disturbances, discussing them with a healthcare professional can help determine whether testing or further evaluation is appropriate.
For a deeper look at this subject, continue with our guide:
→ Menopause: Treatments, Supplements, and Laboratory Testing
What About Women Over 50?
Health priorities can continue to change after menopause and as you move into your 50s.
Cardiovascular health, bone health, metabolic health and age-appropriate screening can become increasingly important considerations.
We've covered this subject separately in:
→ Why Women Over 50 Should Prioritize General Health Checkups
Do Women Over 40 Need Blood Tests Every Year?
Not necessarily.
There isn't one universal list of blood tests that every woman should automatically order every 12 months after turning 40.
How frequently testing is appropriate depends on factors including:
Your age
Medical history
Family history
Menstrual history
Menopause status
Existing health conditions
Medications
Previous laboratory results
Symptoms
Individual risk factors
Someone monitoring an existing condition may need regular testing, while another healthy woman may require less frequent blood work.
A healthcare professional can help determine an appropriate screening schedule for your individual circumstances.
What If You're Tired All the Time?
Fatigue is one of the most common reasons people become interested in blood testing.
But there's no single "fatigue test."
Depending on your circumstances, possible areas of investigation might include:
Complete Blood Count
Iron and ferritin
Thyroid function
Vitamin B12
Vitamin D
Blood glucose
Kidney function
Liver function
If fatigue is your main concern, we've created a separate guide explaining these tests in more detail:
→ Feeling Tired All the Time? 7 Blood Tests That May Help You Find Out Why
Can You Order Your Own Blood Tests?
Depending on the test and applicable requirements, consumers in many parts of the United States can purchase certain laboratory tests directly.
Before ordering, check:
Exactly which biomarkers are included
Whether fasting is required
How the specimen is collected
Where collection takes place
How you'll receive your results
Whether professional interpretation is included
Two tests with similar names don't necessarily include the same biomarkers, so comparing what's actually included can be worthwhile.
USLabTesting helps consumers explore and compare available laboratory testing options.
→ Browse All Lab Tests on USLabTesting
The Bottom Line
Your 40s can be a useful time to become more familiar with health markers such as cholesterol, blood glucose, thyroid function, iron status and general blood counts.
For some women, hormone and nutritional testing may also be relevant depending on symptoms and individual circumstances.
But more testing isn't automatically better.
The goal is to choose tests that provide useful information based on your health, risk factors and symptoms—and to discuss abnormal or concerning results with an appropriately qualified healthcare professional.
If you'd like to compare broader health-testing options:
→ Compare General Health & Wellness Tests
Or continue reading:
→ Why Women Over 50 Should Prioritize General Health Checkups
Important Medical Disclaimer
This article is provided for general informational and educational purposes only and is not intended to provide medical advice, diagnosis or treatment. Screening and laboratory-testing needs vary between individuals. Discuss your health, symptoms, risk factors and laboratory results with an appropriately qualified healthcare professional.