Five labs worth asking about in your 40s
What each one tells you, and why your clinician might order it.
Your 40s are a good time to get a clear baseline. Many changes that show up as “I just feel off” (tiredness, weight shifts, poor sleep, hair changes) have more than one possible cause, and a few common blood tests can help your clinician narrow things down.
Not everyone needs every test. Which labs make sense depends on your history, symptoms, medications and family history, so treat this as a list of questions to bring to your clinician, not a to-do list.
1. Thyroid (TSH, sometimes free T4)
Your thyroid helps regulate energy, temperature, weight and heart rate. Thyroid conditions are more common in women, and symptoms such as fatigue, feeling cold, hair thinning or a racing heart can overlap with perimenopause. A thyroid-stimulating hormone (TSH) test is the usual starting point.
2. Blood sugar (HbA1c and/or fasting glucose)
HbA1c reflects your average blood sugar over roughly the past three months. It’s a common screening test for prediabetes and type 2 diabetes. The U.S. Preventive Services Task Force recommends screening adults aged 35 to 70 who are overweight or have obesity.
3. Cholesterol (lipid panel)
A lipid panel measures LDL, HDL, triglycerides and total cholesterol. Cholesterol often rises around menopause, and heart disease is the leading cause of death for women in the United States. Knowing your numbers early gives you more time to act.
4. Iron stores (ferritin and a complete blood count)
Heavy or irregular periods, which are common in perimenopause, can lower your iron. A complete blood count (CBC) checks for anemia, and ferritin shows how much iron you have stored. Low iron can contribute to tiredness, shortness of breath and hair shedding.
5. Vitamin D
Vitamin D works with calcium to support bone health, which matters more as estrogen declines. Routine testing isn’t recommended for everyone, but your clinician may check it if you have risk factors such as limited sun exposure, certain medical conditions or concerns about bone density.
What about hormone tests?
Many women expect a blood test to “confirm” perimenopause. Hormone levels such as FSH and estradiol can swing a lot from day to day during perimenopause, so a single result often isn’t conclusive. Clinicians usually rely on your age, symptoms and cycle history, and use hormone tests selectively.
Making the most of your results
- Ask what each test is for before you go, and whether you need to fast.
- Ask for the reference range, and what “normal” means for you specifically.
- Keep copies, so you can compare year to year.
- Don’t start supplements or medications based on one number without talking to a clinician.
At NŌVAP, your clinician decides whether labs would help, orders them at a lab near you and explains the results in plain English.
We write about women’s health in plain English. Questions about your own health? Start a visit and talk to a licensed clinician.
This article is for general information only and is not medical advice. It does not replace a consultation with a licensed healthcare provider. Compounded medications, including many NŌVAP protocols, are not FDA-approved. Individual results vary. If you have a medical emergency, call 911.
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