How to Read Your Testosterone Bloodwork Results — What the Numbers Mean

Reading testosterone bloodwork results correctly is a skill most UK steroid users never fully develop. The habit of checking a single number against a reference range and concluding everything is fine misses the majority of what bloodwork is actually telling you. Total testosterone is one data point. Free testosterone, SHBG, LH, FSH and oestradiol together tell a clinical story that total testosterone alone cannot. This guide covers each marker, what it measures, what the numbers mean in context, and what patterns across them should prompt action. All cycle support and PCT compounds referenced throughout are available from the Intex Pharma shop with same day UK despatch.

Total testosterone — what it measures and what it misses

Total testosterone measures the combined concentration of all testosterone in the bloodstream, including testosterone bound to sex hormone-binding globulin (SHBG), testosterone loosely bound to albumin, and free unbound testosterone. The UK reference range varies slightly between laboratories but typically sits between 8.6 and 29 nmol/L for adult men.

The fundamental limitation of total testosterone as a standalone marker is that it tells you nothing about how much testosterone is biologically active. SHBG-bound testosterone is essentially inert. It cannot bind androgen receptors or drive the physiological effects that testosterone produces. Only free testosterone and albumin-bound testosterone are bioavailable. A man with total testosterone of 22 nmol/L and very high SHBG may have significantly less functional testosterone than a man at 15 nmol/L with low SHBG. The number on its own is an incomplete picture.

On a steroid cycle, total testosterone will be elevated in proportion to the dose and ester being used. A mid-cycle reading at peak on 500mg per week of Intex Pharma Testosterone Cypionate should produce total testosterone in the range of 40 to 80 nmol/L. A reading significantly below this range suggests either an underdosed product, a dosing calculation error or an individual metabolism issue worth investigating through repeat testing.

Free testosterone and SHBG — the bioavailability picture

Free testosterone represents the fraction of total testosterone that is not bound to any carrier protein and is immediately available for androgen receptor binding. Most UK lab reports calculate it from total testosterone, SHBG and albumin rather than measuring it directly. The UK reference range using the calculated method typically sits between 0.2 and 0.62 nmol/L, though this varies by calculation method and laboratory.

What matters clinically is not just whether free testosterone sits within the reference range but whether it sits within your individual optimal range. Symptoms of low testosterone despite adequate total testosterone almost always point to either high SHBG binding too much of the circulating total, or elevated oestradiol reducing the effective androgen receptor stimulus.

SHBG naturally rises with age and is also elevated by thyroid dysfunction, liver disease, oestrogen and caloric restriction. It is suppressed by insulin resistance, obesity and exogenous androgens. During a steroid cycle, SHBG typically falls as androgens suppress hepatic SHBG production. This is one reason why free testosterone often improves more proportionally than total testosterone on cycle. Not just because total testosterone rises, but because SHBG simultaneously falls and releases more of it.

LH and FSH — what your pituitary is signalling

Luteinising hormone (LH) and follicle-stimulating hormone (FSH) are produced by the anterior pituitary and form the middle link in the HPG axis. LH tells the Leydig cells to produce testosterone. FSH tells the Sertoli cells to support spermatogenesis. Both should be within the reference range in pre-cycle bloodwork.

Low LH alongside low testosterone before a cycle indicates pre-existing secondary hypogonadism. The problem is at the pituitary or hypothalamic level, not the testes. High LH alongside low testosterone indicates primary hypogonadism. The testes are the problem, not the signalling chain. This distinction fundamentally changes the PCT and recovery picture and should be identified before any cycle begins.

During a cycle, both LH and FSH fall to near-undetectable levels as the exogenous androgen suppresses the HPG axis. This is expected and universal. During PCT with Intex Pharma Nolvadex or Intex Pharma Clomid, rising LH and FSH are the first signs the axis is recovering. They typically precede the rise in total testosterone by two to four weeks as the testes respond to the restored gonadotropin signal. Seeing LH and FSH rise on post-PCT bloodwork while total testosterone is still low is not a sign of failure. It is the recovery sequence working correctly.

Oestradiol — the most misread marker in UK bodybuilding

Oestradiol is the primary oestrogen in men, produced primarily through aromatisation of testosterone by the CYP19A1 enzyme in adipose tissue, muscle and the liver. The reference range for men varies significantly between laboratories. For steroid users, the practically relevant target range on cycle is 80 to 250 pmol/L on the sensitive oestradiol assay.

The standard oestradiol immunoassay used by most UK laboratories was designed and validated for female hormone testing. At the concentrations relevant to men, it loses accuracy and cross-reacts with other steroid molecules. The sensitive oestradiol assay using LC-MS/MS mass spectrometry is the correct test for male hormone monitoring. Medichecks specifies which assay is used on their panels. Always confirm the assay method before interpreting an oestradiol result.

High oestradiol on cycle produces water retention, mood variability and gynecomastia sensitivity. Low oestradiol from aggressive aromatase inhibitor use produces joint pain, mood flatness, reduced libido and cognitive impairment. Both states impair libido, which is why bloodwork rather than symptoms alone should drive any AI dosing decision. Adding more AI to what is already crashed oestradiol makes every symptom worse, not better.

Prolactin — the marker most panels omit

Prolactin is elevated by 19-nor anabolic steroids including Nandrolone and Trenbolone through progestogenic receptor activation at the pituitary. Most standard pre-cycle panels do not automatically include it, but it should be added whenever the planned cycle includes either compound.

Elevated prolactin produces nipple sensitivity and breast tissue changes that closely mimic oestrogen-driven gynecomastia, alongside reduced libido, erectile dysfunction and mood disturbance. These symptoms do not respond to aromatase inhibitors because the mechanism is dopaminergic, not oestrogenic. Intex Pharma Cabergoline is the appropriate intervention for elevated prolactin. Increasing the AI dose in response to prolactin-driven symptoms is one of the most common and costly management errors in UK bodybuilding.

Reading the pattern — what different combinations tell you

Individual markers rarely tell the complete story. The pattern across markers is more informative than any single value, and learning to read combinations is what separates effective cycle management from reactive symptom chasing.

Low total testosterone with low LH and FSH indicates secondary hypogonadism or HPG axis suppression. Low total testosterone with high LH and FSH indicates primary hypogonadism where the testes themselves are failing to respond to adequate pituitary signalling. Normal total testosterone with persistent low-testosterone symptoms points to either high SHBG reducing free testosterone, or oestradiol imbalance affecting androgen receptor sensitivity.

Rising LH and FSH with still-low total testosterone during PCT indicates the axis has restarted but the testes are not yet responding fully. This is the specific scenario where Intex Pharma HCG 5000IU provides direct testicular stimulation that the SERM alone cannot. HCG bypasses the pituitary entirely and acts directly on the Leydig cells, making it the appropriate addition when the signalling chain is working but the end organ is slow to respond.

Flat or falling LH and FSH three to four weeks after the last PCT tablet, despite a completed SERM course, indicates the HPG axis has not yet achieved autonomous function. This warrants extended PCT before adding any other intervention.

When to test and how to time your bloodwork accurately

Timing bloodwork correctly is as important as choosing the right markers. A testosterone reading taken at the wrong time in the injection cycle gives misleading information that can drive poor management decisions.

For mid-cycle testosterone assessment, run a peak reading 24 to 48 hours after the most recent injection and a trough reading immediately before the next scheduled injection. The gap between peak and trough is your amplitude. A large amplitude suggests injection frequency should be increased to produce a flatter, more stable testosterone curve. For post-PCT assessment, run bloodwork four weeks after the last SERM tablet rather than immediately after, as Nolvadex and Clomid continue influencing gonadotropin levels for one to two weeks after the last dose due to their half-lives.

Run all bloodwork fasted. Avoid intense training in the 48 hours before the draw to prevent exercise-induced elevation of liver enzymes and creatinine from confounding the results.

Frequently asked questions

Related guides from Intex Pharma

• Bloodwork before your first steroid cycle — the complete UK panel
• Why testosterone is still low after PCT and what Nolvadex does about it
• Nolvadex or Clomid first for PCT — the sequencing question answered
• Why testosterone crashes between injections and how frequency fixes it
• Best Intex Pharma beginner cycle 2026 — test only, step by step