Hormones · Education
Your hormones, explained.
Hormones are not three numbers on a lab report. They are a conversation happening all over your body, all day long. When you understand who is talking to whom, your labs start to make sense.
This page is for women and men who want to understand their own chemistry before they change it. Read it, bring your questions, and use it as a starting point with your provider.
01 · Where to start
Starting labs, by stage of life.
These are common places to begin a conversation with a licensed provider, not a prescription. Your symptoms, history, and goals decide what is actually ordered. Timing matters too, so ask when in the day (or in your cycle) each test should be drawn.1,2,3
Cycles, fertility, energy, skin, mood.
- Estradiol, progesterone, LH, FSH. Progesterone is usually drawn about a week before your period. LH and FSH are often drawn early in the cycle.
- Total and free testosterone, SHBG, DHEA-S.
- Prolactin.
- AMH if fertility or egg reserve is on your mind.
- Thyroid: TSH, free T4, free T3, TPO antibodies.
- Metabolic: fasting glucose, fasting insulin, HbA1c, lipid panel.
- Basics: CBC, CMP, ferritin, vitamin D, B12.
Perimenopause and the menopause transition.
- Estradiol, progesterone, FSH. These swing day to day in perimenopause, so one number is a snapshot. Symptoms are a big part of the picture.4
- Total and free testosterone, SHBG, DHEA-S.
- Thyroid: TSH, free T4, free T3, TPO antibodies.
- Metabolic and heart: fasting insulin, HbA1c, lipid panel, ApoB, hs-CRP, and Lp(a) at least once.5
- Basics: CBC, CMP, ferritin, vitamin D.
- Ask about a bone density scan as your risk changes.
Postmenopause, heart, bone, and brain.
- Estradiol and progesterone, especially if you use or are considering hormone therapy.
- Total and free testosterone, SHBG, DHEA-S.
- Thyroid: TSH, free T4, free T3.
- Heart and metabolic: lipid panel, ApoB, Lp(a), hs-CRP, HbA1c, fasting insulin.
- Organ health: CMP for liver and kidney function, CBC.
- Vitamin D, plus a bone density conversation.
If you are on birth control or hormone therapy, your results will reflect that. Tell your provider what you take, including how you take it (pill, patch, cream, injection, pellet).
Energy, drive, recovery, fertility.
- Total testosterone, drawn early in the morning. A low result is usually repeated on a second day.1
- Free testosterone and SHBG.
- LH and FSH, which help show whether a low level starts in the testes or in the brain.
- Estradiol (sensitive assay) and prolactin.
- Thyroid: TSH, free T4.
- Metabolic: fasting glucose, fasting insulin, HbA1c, lipid panel.
- Basics: CBC (including hematocrit), CMP, vitamin D.
The slow decline, and the heart.
- Morning total testosterone, free testosterone, SHBG, LH, FSH.
- Estradiol (sensitive assay) and DHEA-S.
- PSA, a conversation to have before any testosterone therapy.
- Heart and metabolic: lipid panel, ApoB, Lp(a) at least once, hs-CRP, HbA1c, fasting insulin.
- Thyroid: TSH, free T4.
- Basics: CBC (hematocrit), CMP, vitamin D.
Prostate, blood, heart, and bone.
- Morning total testosterone, free testosterone, SHBG.
- Estradiol (sensitive assay).
- PSA and a prostate conversation with your provider.
- CBC, with hematocrit watched closely if you use testosterone.
- Heart and metabolic: lipid panel, ApoB, Lp(a), hs-CRP, HbA1c.
- CMP for liver and kidney function, vitamin D, and a bone health conversation.
If you already use testosterone, your provider will usually want hematocrit checked at the start, a few months in, and then about once a year.1
02 · The full cast
More than estrogen, progesterone, and testosterone.
Those three get the attention, but they are only part of the story. Here are the other players your labs may show, grouped by the job they do.
The messengers
Signals from the brain that tell the ovaries, testes, and adrenals what to do.
LH
Pituitary gland
Luteinizing hormone. In women it triggers ovulation and supports progesterone. In men it tells the testes to make testosterone.
High LH with low sex hormones suggests the gland is not answering. Low LH with low hormones points back to the brain.
FSH
Pituitary gland
Follicle-stimulating hormone. It matures eggs in women and supports sperm production in men.
FSH rises as the ovaries slow down, which is why it climbs around menopause.
Prolactin
Pituitary gland
Best known for milk production, but it also affects libido, cycles, and testosterone.
When prolactin runs high, it can quietly suppress LH and FSH, and everything downstream.
The building blocks
Raw materials your body converts into the hormones you know.
Pregnenolone
Adrenals, ovaries, testes, brain
Made from cholesterol. It is the first step toward almost every steroid hormone.
It can head toward progesterone and cortisol, or toward DHEA and the sex hormones.
DHEA and DHEA-S
Mostly the adrenal glands
The most abundant steroid in the blood. DHEA-S is the stable, stored form that labs usually measure.
A precursor to testosterone and estrogen. It naturally declines with age.
Androstenedione
Adrenals, ovaries, testes
A bridge hormone between DHEA and the active sex hormones.
It converts to testosterone, or to estrone with the help of aromatase.
The sex hormones
Yes, everyone makes all of them. The amounts are what differ.
Estradiol (E2)
Ovaries, plus fat and other tissues
The strongest estrogen. Supports bone, skin, brain, mood, blood vessels, and the menstrual cycle. Men need it too, for bone and libido.
Made from testosterone by the enzyme aromatase.
Estrone (E1)
Fat tissue, ovaries, adrenals
A weaker estrogen that becomes the main estrogen after menopause.
Made from androstenedione. It can convert back and forth with estradiol.
Estriol (E3)
Placenta, and liver metabolism
The mildest estrogen. High in pregnancy, low otherwise. Sometimes used in vaginal products.
A downstream product of estrogen metabolism.
Progesterone
Ovaries after ovulation, adrenals
Calms and balances estrogen, supports sleep and mood, and prepares the uterine lining.
It is only made in quantity if you ovulate, which is why it often drops first in perimenopause.
Testosterone
Testes, ovaries, adrenals
Drive, muscle, bone, motivation, and libido, in women and men.
It can become estradiol (aromatase) or DHT (5-alpha reductase).
DHT
Skin, hair follicles, prostate
Dihydrotestosterone, a stronger androgen made from testosterone in the tissues.
Linked to beard and body hair, scalp hair loss, and prostate growth.
The carriers and the partners
Proteins and hormones that decide how much of the rest is actually usable.
SHBG
Mostly the liver
Sex hormone-binding globulin. It carries testosterone and estrogen in the blood. Bound hormone cannot act on your tissues. Free hormone can.
Estrogen-containing medicines and an overactive thyroid can raise it. Insulin resistance, excess weight, and an underactive thyroid can lower it.6,7
Thyroid (TSH, T4, T3)
Pituitary and thyroid gland
Sets the pace of your metabolism, energy, temperature, and heart rate. Free T3 is the active form.
Thyroid status shifts SHBG, which shifts how much free sex hormone you have.
Cortisol
Adrenal glands
Your main stress hormone. It wakes you up, raises blood sugar, and helps manage inflammation.
It shares building blocks with the sex hormones, so long-term stress affects the whole system.
Insulin
Pancreas
Moves sugar into your cells. When it runs high for years, many things change.
High insulin tends to lower SHBG, and in women it is closely tied to higher testosterone, as in PCOS.
AMH
Ovarian follicles
Anti-Müllerian hormone. A rough marker of how many eggs remain.
It falls steadily toward menopause. It does not measure egg quality.
IGF-1
Mostly the liver
A marker of growth hormone activity, which supports repair, muscle, and bone.
Sleep, protein, and some peptides can influence it. Your provider can tell you if it is worth checking.
03 · Relationships
How they talk to each other.
Your steroid hormones all start from cholesterol and pass through a chain of conversions. Change one step and the steps after it change too.
A simplified map. Real pathways have more steps and side roads, and they run in different amounts in the adrenals, ovaries, testes, fat, skin, and brain.
The SHBG seesaw
Most of the testosterone and estradiol in your blood is attached to a carrier, mostly SHBG and albumin. Only a small free portion actually reaches your cells. That is why a "normal" total testosterone can still come with low-testosterone symptoms.
- Estrogen, especially taken by mouth, passes through the liver first and signals it to make more SHBG.7,8
- SHBG holds on to testosterone tightly, so when SHBG rises, less testosterone is left free to reach your cells.6
- Free testosterone drops, even if total testosterone looks the same on paper.
- You feel it: lower drive, energy, muscle tone, or motivation.
This is why the form of a hormone (pill, patch, cream, injection) can matter as much as the dose, and why SHBG and free testosterone belong on the lab order.
From my own labs
When I increased my estrogen, my SHBG went up and my free testosterone went down. I lost the benefits I had been feeling from my testosterone.
Nothing about my testosterone dose had changed. The carrier had changed. With my medical provider, we looked at SHBG and free testosterone together and decided I could stop taking estrogen altogether. I did not personally need it: my body was already making estrogen, from testosterone through aromatase and from my own fat cells.
The result: my SHBG came down and my free testosterone went up. Free testosterone is the portion your tissues, including your muscles, can actually use.
Satine
05 · Next step
Get your labs and hormones in one place.
Lab panels and hormone therapies are available through my private storefront, with a licensed medical team through Altro who reviews your labs and prescribes when appropriate.
- Sign in at portal.satinephoenix.com to see all available offerings.
- Look up the hormones and the lab panels that go with them.
- Not sure where to start? The medical team can help you choose.
Prefer not to go to a lab? For an extra fee, someone can come to your home to collect your blood sample.
Numbered links on this page point to the sources on our Citations page.
This page is for education only and is not medical advice, diagnosis, or treatment. Lab suggestions are general starting points. Your licensed provider decides which tests and treatments are right for you. Reference ranges and recommendations change over time. Please read the medical disclaimer.