Blood tests at the 3-month review: when they help and what we check

For most women over 45, menopause is diagnosed from symptoms and menstrual pattern. Blood tests are not needed to start HRT, and a hormone test for menopause can even mislead because levels swing so much in perimenopause. Where bloods earn their keep is later: at the 3-month review, if symptoms have not improved as expected, a targeted panel often explains why.

This article describes the tests we typically check at that point, why we choose them, and the situations where bloods are useful earlier than 3 months.

Why no bloods at the start, usually

If you are over 45 and your symptoms and menstrual pattern fit menopause, NICE guidance is clear that an FSH blood test is not required and can even be misleading. Hormone levels fluctuate widely in perimenopause; a single low FSH does not rule menopause out, and a single high one does not prove it. Treatment is symptom-led. Starting HRT, then reviewing how you feel, is a better test of menopause than a blood test is.

Why the 3-month review is the natural point to check bloods

Most women notice flushes and sweats easing within a few weeks of starting HRT. Sleep, mood and energy usually take longer, often a couple of months. By three months, the treatment has had a fair chance to work, and at the review we can see what has improved and what has not. If fatigue, brain fog or low mood are still bothering you despite a sensible HRT dose, that is the moment a small targeted panel can pay off.

The panel we typically check

Where symptoms persist at the 3-month review, our usual first panel is a small set of common nutritional checks plus, where relevant, a check that your HRT is being absorbed:

• Vitamin B12 and folate, because deficiency causes fatigue, low mood, and cognitive symptoms that overlap directly with menopause.

• Ferritin (iron stores), often low in women who have had years of heavy or irregular periods, and a common cause of fatigue and breathlessness.

• Vitamin D, frequently low in the UK and linked to mood, energy, bones, and muscle symptoms.

• Estradiol level, if you are using transdermal HRT, to check how much is getting through the skin. Aiming to keep the level in the right range often guides whether to adjust the dose or the product.

Other tests get added when the symptom picture points there: thyroid function if there is unexplained fatigue, weight change or temperature intolerance; lipids and glucose if there is a cardiovascular question; liver tests if there is a reason to. We test when the result will change what happens next.

When bloods help earlier, not at three months

Some situations call for bloods at the start rather than waiting:

• If you are under 45, particularly under 40, where early menopause and premature ovarian insufficiency need to be specifically considered.

• If your periods have stopped after a hysterectomy and ovaries-conserved surgery, where there is no menstrual marker to follow.

• If your symptoms are atypical or there is something in the history that does not fit straightforward menopause.

• Before starting testosterone for low desire, where a baseline blood test of testosterone and a related measure gives us a reference point.

• If you have an existing condition (thyroid, anaemia, diabetes) that needs its own monitoring.

Outside these, waiting until three months and testing only if needed avoids tests that would not change anything.

What about repeat hormone tests on continuing HRT?

On standard tablet or patch HRT in a settled patient, repeat hormone levels are not usually required. On transdermal HRT, particularly when symptoms suggest the dose may not be enough, checking estradiol levels can help work out whether the skin is absorbing well. The level is interpreted alongside how you feel; a number on its own does not justify changing a dose that is working.

How results change the plan

A low B12, low folate, low ferritin or low vitamin D usually responds quickly to supplementation, and the lift in fatigue, mood or energy that follows often clarifies how much of the original symptom was menopause and how much was deficiency. A low estradiol on transdermal HRT may prompt a dose increase or a switch to a different product. A normal panel still helps; it lets us focus on adjusting the HRT, considering a non-hormonal addition, or looking at other contributors such as sleep, alcohol, stress, or a coexisting medical issue.

The honest summary

Blood tests at the start of HRT are rarely needed. At the 3-month review, if symptoms have not improved as they should, a small targeted panel of vitamins, iron and (on transdermal HRT) estradiol level often explains the gap, and is cheap to do and easy to act on. Where the picture or the history calls for earlier testing, we do it. The principle is the same throughout: tests are a tool, not a default, and they earn their place by changing what we do next.

Ready to start?

If you want to move from reading to acting, the next step is a short assessment with a doctor on the GMC GP Register. It takes about ten minutes and tells you whether HRT is right for you.

Begin your assessment at this link. Online or in person at Westfield London.