The Blood Tests Your Doctor Isn't Ordering (But Should) for Perimenopause

You know something is off. The sleep disruptions, the mood shifts, the fatigue that no amount of coffee seems to touch. So you go to your doctor. They order some labs. Everything comes back "normal." And you're left sitting there thinking, did I imagine all of this?

You didn't. And you're far from alone. One of the most common frustrations during perimenopause is being told your labs look fine when your body is clearly telling a different story. The problem isn't you. The problem is that the standard blood work most doctors order was never designed to catch the hormonal shifts of perimenopause.

This guide is here to change that. By the time you finish reading, you'll know exactly which perimenopause blood tests to ask for, what the results actually mean, and how to have a productive conversation with your provider about getting the full picture.

Why standard blood work often misses perimenopause

Most routine physicals include a basic metabolic panel. That covers things like your blood sugar, kidney function, and electrolytes. It's useful, but it tells you almost nothing about your reproductive hormones.

Even when hormones are tested, there's a fundamental challenge. During perimenopause, your hormone levels fluctuate wildly. Estrogen can swing from very high to very low within the same week. Progesterone may be barely detectable one month and closer to normal the next. FSH rises and falls in unpredictable waves. A single blood draw captures one moment in time. If that moment happens to land on a day when your hormones are in a temporary "normal" range, the results will look unremarkable.

This is why so many people are told they're fine when they feel anything but. It's not that the test was wrong. It's that a single snapshot can't capture a moving target. Your provider needs to understand this context, and you need to know which tests paint a more complete picture.

There's another layer to the problem. Many of the symptoms of perimenopause overlap with other conditions. Thyroid disorders, iron deficiency, vitamin deficiencies, and blood sugar imbalances can all produce fatigue, brain fog, mood changes, and sleep disruption. A thorough panel doesn't just look for perimenopause. It rules out the other possibilities that could be contributing to how you feel.

The complete hormone panel to request

Here's the full list of perimenopause blood tests to ask for at your next appointment. For each one, you'll find what it measures, what typical ranges look like, and what patterns suggest during perimenopause.

FSH (Follicle-Stimulating Hormone) FSH is produced by your pituitary gland and signals your ovaries to produce estrogen. As your ovaries become less responsive during perimenopause, your brain compensates by producing more FSH. A normal premenopausal FSH is typically under 10 mIU/mL. During perimenopause, you may see levels between 10 and 25 mIU/mL, though they can spike higher and then drop again. Consistently elevated FSH above 25 mIU/mL suggests you're moving closer to menopause. Remember that a single normal reading does not rule out perimenopause, because FSH fluctuates significantly during this transition.

Estradiol (E2) Estradiol is the primary form of estrogen your body produces during your reproductive years. In a regular cycle, estradiol levels range from about 30 to 400 pg/mL depending on where you are in your cycle. During perimenopause, levels can swing even more dramatically, sometimes surging higher than they ever did before, then dropping to postmenopausal ranges within days. A low estradiol reading (under 30 pg/mL) paired with elevated FSH is a strong indicator, but again, one test doesn't tell the whole story.

Progesterone (Day 21 Testing) Progesterone rises after ovulation, typically peaking about seven days before your next period. This is why it's best tested around day 21 of your cycle (if you're still cycling). A level above 5 ng/mL generally confirms ovulation occurred. During perimenopause, you may have cycles where you don't ovulate at all, which means progesterone stays low throughout the month. Low progesterone relative to estrogen is a hallmark of early perimenopause and can drive symptoms like heavy periods, anxiety, and disrupted sleep.

TSH, Free T3, and Free T4 (Thyroid Panel) Thyroid disorders mimic perimenopause so closely that testing is essential. Hypothyroidism causes fatigue, weight gain, brain fog, and depression. Hyperthyroidism causes anxiety, heart palpitations, and sleep disruption. TSH between 0.4 and 4.0 mIU/L is considered normal, but many functional practitioners note that optimal TSH sits between 1.0 and 2.5. Request Free T3 and Free T4 in addition to TSH. These measure the active thyroid hormones circulating in your blood and can reveal problems that TSH alone might miss.

Testosterone (Total and Free) Testosterone isn't just a male hormone. It plays a key role in your energy, libido, muscle maintenance, and mood. Total testosterone in premenopausal women typically ranges from 15 to 70 ng/dL. Free testosterone (the biologically active portion) is usually between 0.5 and 5.0 pg/mL. Declining testosterone during perimenopause can contribute to low motivation, reduced sex drive, and difficulty building or maintaining muscle. Knowing your baseline helps your provider understand the full hormonal picture.

DHEA-S DHEA-S is a precursor hormone produced by your adrenal glands that converts into both estrogen and testosterone. Normal ranges for adult women are roughly 35 to 430 mcg/dL, declining with age. Low DHEA-S can compound the effects of declining ovarian hormones and may point to adrenal fatigue. It's an often-overlooked marker that adds important context.

Vitamin D Vitamin D supports bone health, immune function, and mood regulation. Levels between 30 and 50 ng/mL are generally considered sufficient, though some practitioners aim for 40 to 60 ng/mL. Deficiency is extremely common, especially in perimenopause, and can worsen fatigue, mood changes, and bone loss. This is one of the most actionable tests because supplementation is straightforward and effective.

Fasting Insulin and Glucose Insulin resistance becomes more common during perimenopause as estrogen levels decline. Fasting glucose should be under 100 mg/dL. Fasting insulin below 10 uIU/mL is generally considered healthy, with optimal closer to 5. Elevated fasting insulin, even with normal glucose, can be an early warning sign of metabolic changes. It can also explain stubborn weight gain around the midsection, energy crashes after meals, and increased sugar cravings.

Complete Blood Count (CBC) A CBC provides a broad look at your blood cells, including red blood cells, white blood cells, and platelets. It can reveal anemia (common in perimenopause due to heavy periods), infection, and other underlying issues. If your hemoglobin or hematocrit is low, that alone could explain significant fatigue.

Iron and Ferritin Iron studies go beyond the CBC. Ferritin measures your stored iron, and it's the most sensitive early marker of depletion. Many providers consider ferritin "normal" at 12 ng/mL, but optimal levels for energy and function are closer to 50 to 100 ng/mL. If you're having heavy or prolonged periods during perimenopause, your iron stores may be dropping faster than your body can replenish them.

Vitamin B12 B12 supports nerve function, red blood cell production, and energy metabolism. Levels below 400 pg/mL can contribute to fatigue, brain fog, tingling in your hands or feet, and mood changes. Deficiency is more common than many people realize, especially if you eat limited animal products or take certain medications like proton pump inhibitors or metformin.

Cortisol (Morning Draw) Cortisol is your primary stress hormone, and it has a natural rhythm. It should peak in the early morning and taper through the day. A morning cortisol draw (ideally between 7 and 9 a.m.) with results between 6 and 23 mcg/dL is considered normal. Very high or very low morning cortisol can signal adrenal dysfunction, which often worsens during perimenopause because your adrenals are tasked with picking up some of the hormone production your ovaries are scaling back.

How to read your results

When your results come back, resist the urge to look only at whether each number falls inside the "normal" reference range. Lab reference ranges are based on the general population, which includes people of all ages and health statuses. What's statistically normal and what's optimal for how you feel can be very different things.

Here are some patterns to look for.

If your FSH is elevated and your estradiol is low, that combination strongly suggests perimenopause. If FSH is high but estradiol is also high, you may be in the earlier stages when your body is producing extra estrogen to compensate for ovaries that are becoming less responsive.

If your TSH is above 2.5 with low Free T3 or Free T4, thyroid dysfunction could be contributing to your symptoms, even if your TSH is technically within the reference range. Thyroid and perimenopause can also coexist, so addressing one doesn't necessarily resolve the other.

If your ferritin is below 50 even though your iron and hemoglobin are "normal," depleted stores could be a significant factor in your fatigue. This is one of the most commonly missed findings in routine blood work.

If your fasting insulin is above 10 with normal glucose, you may be in the early stages of insulin resistance. Your body is working harder to keep blood sugar stable, and that metabolic strain can show up as weight changes, energy crashes, and increased cravings.

The most important thing to remember is that these tests work best as a group. No single number tells the complete story. The relationships between your hormones, thyroid markers, metabolic indicators, and nutrient levels paint a picture that is far more useful than any individual result.

How to ask your doctor for these tests

Track your symptoms alongside your labs

Lab results give you a snapshot. Symptom tracking gives you the story around that snapshot. When you combine the two, you and your provider have something genuinely powerful to work with.

For example, if your estradiol is low and your symptom log shows two weeks of disrupted sleep, increased hot flashes, and persistent brain fog, the connection between the hormone level and your lived experience becomes very clear. If your ferritin is borderline and your tracking data shows that your fatigue worsens during and right after your period, that points directly to a link between heavy bleeding and iron depletion.

PeriPlan's daily check-in makes this kind of tracking simple. Logging your sleep quality, mood, energy, and key symptoms takes under two minutes and builds a picture over time that becomes genuinely useful context for interpreting your lab work. When you can walk into an appointment with both your blood work and several weeks of tracked symptom data, you move the conversation from guesswork to evidence.

Consider timing your blood tests strategically. If you're still cycling, testing FSH and estradiol on day 3 of your cycle and progesterone around day 21 gives the most informative readings. Mark the test dates in your symptom log so you can cross-reference how you were feeling on the day of the draw.

You are not imagining your symptoms. You are not overreacting. And you deserve more than a dismissive "everything looks normal" when your body is telling you otherwise.

Arming yourself with knowledge about which perimenopause blood tests to ask for is one of the most powerful things you can do for your own health right now. You don't need to become a lab technician. You just need to know enough to ask the right questions and to recognize when the answers don't match your experience.

Your body is going through a real transition. You deserve real answers.

This content is for informational purposes only and does not replace medical advice. Always consult your healthcare provider about your specific situation.