I Googled ‘fertility test’ and bought a panel, now what?
What your ‘fertility test’ really tells you, and what it doesn’t.
In this issue
What your “fertility test” panel is actually measuring (and what it isn’t)
The hormones that never make it onto the generic panels but change the story
Two women who bought the same “fertility test” and what that panel misses in both their stories.
What you can and cannot answer about “Am I fertile?” from one panel
You’re thinking about a baby.
Not IVF, maybe egg freezing, or not. You just want a steer: Am I basically okay? What labs will give me something I can plan around? And, when you get down to it, an answer to the question: Am I fertile?
What You Actually Get When You Buy A “Fertility Test”
So you do some late‑night shopping on Google and type in “fertility test female”.
Which is exactly what I did writing this piece, to gauge the latest marketing trends.
Same search term, three different “fertility tests” popped up on the first page (I’m not talking here about the IVF work‑up panels and tests that also appeared, which are a different kettle of fish for another time).
First one: a CD3 (cycle day‑3) panel with estradiol, FSH, LH, an FSH:LH ratio, testosterone.
Another one: FSH, LH and estradiol on a random day, progesterone with a note to test 7 days before your period, plus TSH.
And yet another: FSH, LH, “estrogen”, progesterone, testosterone, SHBG, with AMH as an optional extra.
You’d expect there to be one clear, evidence‑based “fertility hormone panel” everyone agrees on.
Instead, what you actually get is a lucky dip.
Hormones Don’t Work Solo: Meet The Waterfall
Let’s say you go ahead and order one of these panels.
There are two big things to keep in mind before you start reading off individual hormones.
First, hormones don’t work as solo acts. They behave more like a waterfall: one signal tumbles into the next, and the shape of the flow downstream depends on what’s happening upstream. If you only measure a random selection of hormones, you’re only ever seeing pieces of that cascade, not how it actually runs as a whole.
Second, the nature of that cascade is dictated by what’s feeding into it. Think of the top of a waterfall and everything that pours in before the water tips over the edge: blood sugar and insulin, thyroid function, nutrient status, inflammation, stress, sleep, your overall metabolic state.
Your reproductive physiology is not separate from the rest of you. It’s in constant conversation with all of that, which means those “fertility hormones” are really just one part of a much bigger system.
With that in mind, let’s look at the hormones your panel might show you, and the ones it usually doesn’t.
The Main Quartet: The Cast of Hormones At Centre Stage
If this looks long, you can skim it. The point is to see who’s who and when they’re worth testing, not to memorise every hormone.
If hormones live in a cascade, it helps to meet (and not learn by heart!) the main characters at the two points where they tell us the most: early in the cycle, and about a week after ovulation. Not the random handful your panel happened to pick, but the core group I actually care about, and when they’re worth testing.
CD2/3 (Cycle Day 2–3): Getting The Follicle Going
FSH and LH
These are signals sent out from the pituitary gland under your brain, all the way down to your ovaries.
They say, “Grow a follicle” (FSH) and “Now your follicle has grown, it’s time to release the egg and make progesterone so the endometrium can carry a baby” (LH).
Estradiol
This is the follicle talking back.
The follicle grows, makes estradiol, and that estradiol sends messages back up to the brain: “Thanks, I got the message, this one is growing nicely, you can ease off the FSH.”
Best tested: FSH, LH and estradiol together on cycle day 2–3 (CD2/3).
7DPO (7 Days After Ovulation): Did You Ovulate, And Can You Hold It?
In the middle of the cycle, rising estradiol helps the brain send a big pulse of LH – the LH surge – which is the push that actually triggers ovulation. We don’t usually catch that surge in bloods, but we do care about what happens in the week afterwards.
Progesterone (with estradiol again)
Once you’ve ovulated, the emptied follicle transforms into the corpus luteum. Its all‑mportant job is producing progesterone, which we need in decent amounts to stabilise and mature the lining to welcome a potential embryo. Checking estradiol again at this point helps show how well that luteal phase is being supported.
Best tested: estradiol and progesterone together about a week after ovulation – a proper mid‑luteal sample, not a guess based on “7 days before your next period”.
The Supporting Players: The Hormones Your Panel Skipped
Prolactin
The “mother’s milk” hormone. Already? you’re thinking.
Prolactin, another pituitary hormone like FSH and LH, does more than nudge breasts to make milk; it also has background jobs in immunity and metabolism. From a baby‑making point of view, what we care about is it not being too high at the wrong time.
Elevated prolactin changes the way the pituitary behaves, which in turn affects FSH and LH signalling to the ovaries. With these three effectively talking over each other, the brain‑to‑ovary‑to‑uterus cascade starts to lose its smooth flow.
Best tested: morning, CD2/3.
TSH
TSH is another pituitary signal, this time to the thyroid gland.
From a baby‑making point of view, an overly high or low TSH can affect ovulation, luteal phase quality, and pregnancy outcomes.
A “normal” TSH on its own doesn’t tell us how well your actual thyroid hormones (T4 and T3) are doing their job, or whether antibodies are quietly stirring the pot. That’s a whole future issue in itself.
Best tested: any morning.
AMH
AMH is made inside the ovary by small growing follicles.
Bottom line: it’s an imprecise tracker of ovarian reserve and is most meaningful when very high or very low, or when you’re actively considering IVF or egg freezing.
Best tested: any day of the cycle.
Androgens: DHEAS, Testosterone, Androstenedione
These are the hormones you need in the right range for muscle, mood, libido and early follicle development.
Testosterone and androstenedione come mostly from the ovaries and adrenals. When they’re high, we think about a PCOS‑type pattern where follicles hover in the almost‑ready stage instead of actually ovulating; when they’re low for your age, we start asking about things like diminished ovarian reserve, long‑term pill use, under‑fuelling or other reasons overall output might be down.
DHEAS is mainly adrenal. When it’s high or low alongside the ovarian androgens, it points to what might be going on with your stress and blood sugar picture.
Best tested: morning, usually CD2/3 alongside the others.
SHBG
Made in the liver, SHBG is the taxi that picks up estradiol and testosterone and controls how much is actually free to act on tissues.
When it’s low, you tend to have more free androgens around, which can hint at insulin issues, thyroid problems or background inflammation. When it’s very high, you may not have enough free hormone to work with.
Best tested: CD2/3, with the rest of the main panel.
The Waterfall At Work: Gentle Stream Or Niagara?
Taken together, these hormones give us a far better sense of the whole cascade than any lucky‑dip panel ever will.
You can think of it like this:
brain: FSH, LH, prolactin, TSH
ovaries and adrenals: estradiol, progesterone, testosterone, androstenedione, DHEAS, AMH
liver and thyroid: SHBG and the thyroid hormones sitting behind TSH
uterus: the endometrium responding (or not) to all of the above
Looked at as a team, they start to show you whether your hormonal waterfall is flowing like a gentle tropical stream – clear signals, solid ovulation, a decent luteal phase – or crashing around more like Niagara Falls, with the messages tangled and the lining getting mixed instructions.
That’s the level we need to be at before we can say anything more useful than “your panel was in range” or “a couple of numbers were off”.
Two Women, One Panel, Very Different Stories
Let’s say you ordered that middle‑of‑the‑road panel:
FSH, LH, estradiol on a random day, progesterone “7 days before your period”, plus TSH.
On paper it looks decent. Brain signals, a sex hormone or two, something for thyroid.
In reality, it leaves huge gaps.
Scenario 1: The Hypothalamic Amenorrhoea Athlete
She’s early 30s, trains hard, eats “clean” but not quite enough, periods have gone from light to missing.
On that panel you might see:
FSH: low‑normal or low
LH: low
Estradiol: low
Progesterone: low or unclear (because the blood wasn’t taken mid‑luteal)
TSH: “normal”
The report says “within range” or “slightly low oestrogen”.
What you can tell: the whole reproductive cascade is dialled down. The brain is not pushing, the ovary isn’t answering.
What you can’t tell from this panel:
that she’s under‑fuelling relative to her training
what her adrenal stress hormones look like
whether her androgens are low for age
whether iron, B12, vitamin D, thyroid hormones or blood sugar are telling the brain “not a good time for a baby”
To really understand her, you’d need at least:
properly timed CD2/3 FSH, LH, estradiol
prolactin and androgens (total and free testosterone, DHEAS)
a properly timed mid‑luteal progesterone + estradiol if she’s cycling at all
plus those upstream labs at the top of the waterfall: iron studies, B12, vitamin D, glucose/insulin, thyroid hormones, maybe a cortisol pattern
Same “fertility panel” result; completely different level of understanding.
Scenario 2: A PCOS‑Type Pattern
She’s late 20s or early 30s, cycles are long or irregular, maybe acne, weight that’s hard to shift, family history of “bad periods”.
On the same panel you might see:
FSH: “normal”
LH: “normal” or a bit higher than FSH, still in range
Estradiol: “normal”
Progesterone: low or ambiguous if it wasn’t truly mid‑luteal
TSH: “normal”
The report is mostly green, maybe with a vague “consider PCOS”.
What you can tell: timing is off, and there’s no obvious ovarian failure or indicating thyroid problem.
What you can’t tell:
whether androgens are actually high (no testosterone, DHEAS, androstenedione, free T)
whether insulin resistance is driving things (no glucose, no insulin)
whether SHBG is low, letting more free androgens roam
whether AMH is high in a PCOS‑ish way or comfortable for her age
whether she’s ovulating regularly – one mistimed progesterone cannot answer that
To flesh out her picture, you’d want:
CD2/3 androgens: total + free testosterone, DHEAS, ± androstenedione
SHBG and AMH (especially if egg freezing or IVF is on the table)
a properly timed mid‑luteal progesterone + estradiol on at least one cycle
fasting glucose and insulin, lipids, liver function, inflammatory markers – the top‑of‑the‑waterfall labs that tell you how hard her ovaries are having to swim
So… Am I Fertile?
Those two women’s panels suggest potential fertility issues, but that’s only half the story.
What if your own results come back “in range”? Does that answer the question? Not really.
An “in range” panel still can’t tell you:
whether you actually ovulated that cycle (you’d need things like temps or LH patterns for that)
whether your luteal phase is strong enough to hold a potential pregnancy
whether there are upstream issues – blood sugar, thyroid, nutrients, inflammation, stress – shaping that cascade
“In range” just means “inside the lab’s statistical bucket for this population, who aren’t necessarily trying to get pregnant”. It does not automatically mean “optimal for getting and staying pregnant”, or “no other underlying issues here”.
You can have every hormone in the “normal” column and, for example, still be missing ovulation some cycles, have a thyroid that’s a bit too slow for easy conception, or be dealing with blood sugar and inflammation patterns that drag on egg quality.
Before you file that lab report away
One panel is a snapshot, not the full story.
The real drivers of fertility sit upstream – in the labs that track blood sugar, thyroid, nutrients, inflammation and stress.
Those upstream signals shape the whole waterfall: how your brain talks to your ovaries, how your ovaries talk to your lining, and how reliable that cascade feels cycle after cycle.
“In range” hormones aren’t the same as “set up for getting and staying pregnant” if the upstream story is off.
The most useful labs are personalised: chosen for your health history and story, not whatever fits on a generic “fertility test” order form.
Warmly, Sonja
Work with me: If you’d like help turning your lab results, genetics and health history into a practical preconception plan, you can read more and book a free 15‑minute call here.
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Great and beautifully written guide to fertility tests!
I’m grateful to have such a loyal reader! So will your future babies!