NICE guideline NG23 tells GPs not to use FSH to diagnose perimenopause in women aged 45 and over. They are right that a single FSH reading is unreliable. But they are wrong that testing has no value. A comprehensive panel covering hormones, thyroid, metabolic health, and nutrients reveals what symptoms alone cannot: which systems are driving your experience and what to do about them. A panel like the TrueVitals Ultimate covers 114 biomarkers across all of these systems.
NICE NG23 (Menopause: identification and management, updated November 2024) makes three specific recommendations about blood testing:
Diagnose clinically based on symptoms and cycle changes. Do not use FSH blood tests. NICE considers symptoms sufficient for diagnosis at this age.
FSH may be offered to help confirm a suspected diagnosis, alongside clinical assessment.
Two FSH tests 4 to 6 weeks apart are required. POI affects approximately 1 in 100 women under 40 and requires specialist management.
The reasoning is sound but the conclusion is incomplete. FSH fluctuates wildly during perimenopause. It can be elevated one week and normal the next. A single FSH reading genuinely cannot confirm or rule out perimenopause. NICE is right about that. But the guideline addresses only FSH for diagnosis. It does not address the broader value of comprehensive testing: establishing a hormonal baseline for HRT planning, distinguishing perimenopause from thyroid dysfunction, identifying nutrient deficiencies that compound symptoms, and measuring the metabolic and cardiovascular changes that accelerate during the transition.
The guideline is about diagnosis. Comprehensive testing is about understanding. They are different things.
These are not reasons to override your GP. These are reasons to complement a symptom-based diagnosis with data that symptoms alone cannot provide.
Fatigue, weight gain, brain fog, mood changes, hair thinning, poor sleep. These are perimenopause symptoms. They are also thyroid dysfunction symptoms. And iron deficiency symptoms. And vitamin D deficiency symptoms. And insulin resistance symptoms. Without testing, the attribution is assumption. One study suggested that up to 20% of women over 60 have thyroid dysfunction, and the process often begins in the 40s. A comprehensive panel distinguishes between these overlapping causes in a single blood draw. Thyroid blood test guide.
If you start HRT in 2 years, your prescriber will benefit enormously from knowing your pre-HRT hormonal levels. Where was your oestradiol before it declined? What was your testosterone? Was your thyroid already borderline? These data points shape the type, dose, and route of HRT. Without a pre-treatment baseline, prescribing is guided by population averages rather than your individual starting point.
Oestrogen protects cardiovascular health. As it declines, ApoB, triglycerides, and hs-CRP can shift unfavourably. By 55, women's cardiovascular risk equals men's. CVD kills more UK women than all cancers combined. Measuring advanced lipids (ApoB, Lp(a)) now, while oestrogen is still partially protective, gives you the earliest possible read on your cardiovascular trajectory. Cardiovascular guide.
The perimenopausal decline in oestrogen impairs insulin sensitivity. Weight redistribution to the abdomen accelerates. Fasting insulin and HOMA-IR detect this metabolic shift years before HbA1c catches it. If you're gaining weight around your midsection despite unchanged diet and exercise, insulin resistance is a likely contributor and it's measurable right now. Prediabetes guide.
A single snapshot has limitations. NICE is right about that. But serial testing (every 6 to 12 months) builds a picture that single tests cannot. Rising FSH alongside declining oestradiol alongside stable thyroid confirms hormonal perimenopause. Rising FSH alongside elevated Anti-TPO alongside declining Free T3 reveals a combined hormonal and thyroid picture. The trend over time is far more informative than any single reading.
The TrueVitals Ultimate panel covers the full hormonal profile (FSH, LH, oestradiol, progesterone, testosterone, SHBG), complete thyroid with antibodies, advanced cardiovascular, metabolic depth, and nutrient stores. 114 biomarkers. Results in 48 hours. £349.
Lola Health estimates 13 million women in the UK are currently in perimenopause or menopause. The majority struggle to get a clear diagnosis. Part of the problem is the symptom overlap between perimenopause, thyroid disease, iron deficiency, and vitamin D depletion.
Consider this scenario: a 46-year-old woman presents with fatigue, weight gain, brain fog, mood changes, and irregular periods. Her GP says it's probably perimenopause and offers HRT. But her symptoms are actually driven by Hashimoto's thyroiditis (elevated Anti-TPO, declining Free T3) compounded by low ferritin (28 µg/L, "in range" but functionally depleted) and vitamin D deficiency (32 nmol/L). HRT will not fix thyroid dysfunction. HRT will not replenish iron. HRT will not correct vitamin D. Without testing, she starts HRT, her symptoms partially improve (oestrogen does help some things), and she assumes the remaining symptoms are just "how it is now." They're not. They're treatable. They just weren't tested.
The reverse also happens. A woman with genuine perimenopause is told her thyroid is "normal" (based on TSH only). She supplements vitamin D and iron. Her symptoms persist because the underlying hormonal shift was never addressed with HRT. Testing identifies the actual driver. Treatment can then target the actual cause.
Not just FSH. Not just hormones. The full systems that drive, mimic, and compound perimenopausal symptoms.
FSH, LH, oestradiol, progesterone. Establish where you are in the transition. Progesterone often drops first (anovulatory cycles). Oestradiol fluctuates unpredictably.
Testosterone, SHBG, free testosterone. Female testosterone affects energy, mood, libido, and body composition. NICE NG23 recommends testosterone for menopausal women if HRT alone doesn't help libido.
TSH, Free T4, Free T3, Anti-TPO, Anti-Tg. Distinguishes thyroid dysfunction from perimenopause. Catches Hashimoto's years before TSH moves.
HbA1c, fasting glucose, fasting insulin, HOMA-IR. Oestrogen decline impairs insulin sensitivity. Catches metabolic shift early.
ApoB, Lp(a), HDL, triglycerides, hs-CRP. Track cardiovascular protection declining as oestrogen drops.
Ferritin, vitamin D, B12, folate, zinc. Heavy perimenopausal periods deplete iron. Vitamin D is critical for bone protection as oestrogen declines.
Timing note: If you're still having periods, test hormones on day 2 to 5 of your cycle (FSH, LH, oestradiol) and day 21 (progesterone). If cycles are irregular, test any day. The irregularity itself is informative. For all other markers, timing within the cycle doesn't matter. A fasting morning draw gives the most accurate metabolic and lipid readings.
The report doesn't just list hormone levels. It analyses the pattern between hormones, thyroid markers, metabolic markers, and nutrients using AI cross-system analysis. It identifies which systems are contributing to your symptoms and provides specific, evidence-based recommendations. A medical professional reviews every report before it reaches you.
The result is a document you take to your GP or menopause specialist. You're not asking them to diagnose perimenopause. NICE says they can do that clinically. You're giving them the metabolic, thyroid, and nutritional data they don't have, so they can prescribe HRT with precision, identify thyroid dysfunction if present, and address nutrient deficiencies that worsen symptoms regardless of cause.
Retest in 6 to 12 months. The comparison between tests shows how the transition is progressing, whether HRT is working, and whether your thyroid, metabolic, and nutrient status has shifted. That longitudinal picture is the most valuable thing comprehensive testing provides.
114 biomarkers. Hormones, thyroid, cardiovascular, metabolic, and nutrients. The data your GP doesn't have. Results in 48 hours.
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