Timing matters when it comes to hormone testing. Your hormone levels naturally rise and fall throughout your menstrual cycle, so testing at the right time helps us give you the most accurate and meaningful results.

Test on day 3 of your cycle (day 1 is the first day of bleeding). This is when your baseline hormone levels are most stable, which allows doctors to interpret your results accurately. If day 3 doesn't work for you, days 2–4 are also fine.

Your hormones follow a predictable pattern during a typical 28-day cycle. Here's what's happening:
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Your period begins, and hormone levels are at their lowest. Oestrogen and progesterone have dropped, which triggered your period.
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Follicle-stimulating hormone (FSH) gently rises to stimulate your ovaries to develop follicles. As a follicle matures, it produces oestrogen, which steadily increases. Luteinising hormone (LH) remains relatively low.
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Day 3 sits right in this early phase — before the hormonal surges begin — giving us a more reliable "baseline" reading of your FSH, LH, and oestrogen levels.
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LH surges dramatically, triggering ovulation. Oestrogen also peaks just before this surge. This is the most fertile point of your cycle. Day 14 is approximate, but it can vary significantly, since ovulation on day 14 assumes a 28-day cycle, which many women don't have.
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After ovulation, the empty follicle becomes the corpus luteum and produces progesterone. Progesterone rises and peaks around days 19–21, preparing the uterine lining for potential pregnancy. If pregnancy doesn't occur, hormone levels drop, and your period begins again.

When these hormones are measured at their baseline, your results can provide more meaningful insights into ovarian function and hormonal patterns.

We know cycles aren't always straightforward. Here's guidance for different situations:
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We recommend waiting until you have a period, then testing on day 3 of that cycle. This gives us the most valuable insights.

If you're experiencing frequent bleeding and can't determine when your period starts and ends, aim to test on a day when you're not actively bleeding.

Good to know: If you have irregular periods combined with symptoms like acne, excess body hair (hirsutism), or unexplained weight gain, a PCOS-focused test might give you more relevant insights.

You can take this test anytime. However, without a regular cycle, it may be harder for our doctors to interpret your FSH, LH, and oestrogen results in context. We'll still provide your results with as much context as we can, and your results may help identify reasons for absent periods.

We don't recommend this test if you're using hormonal contraceptives — including the pill, patch, injections, implant, or hormonal coil (IUS/Mirena).
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These methods suppress your natural ovulation cycle and alter your hormone levels, which means the results are unlikely to reflect your natural hormonal patterns.

Wait at least 3 months before taking this test. This allows time for your natural cycle to return and your hormone levels to stabilise.
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If you were using the contraceptive injection: We recommend waiting 12 months, as the injection can take longer to leave your system.
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Once you've had a natural period, test on day 3 of your cycle.

Breastfeeding naturally increases prolactin levels, which suppresses ovulation and affects your other hormone levels. This makes it difficult to accurately interpret your results.
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We recommend waiting until you've stopped breastfeeding before taking this test. The more frequently you breastfeed, the more pronounced the hormonal effects.

If you're experiencing symptoms you're concerned about while breastfeeding, speak with your GP — they can advise on appropriate testing.

Please don't take this test if you're pregnant. Pregnancy dramatically changes your hormone levels, so the results are unlikely to be meaningful for assessing your reproductive hormone health.

We don't recommend testing oestradiol levels while on HRT. Your levels will fluctuate throughout the day based on when you take your medication, and these readings may not reliably indicate how well your HRT is working for you.
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If you have concerns about your HRT, please discuss them with your prescribing doctor, who can assess your symptoms and adjust your treatment accordingly.

Your hormone levels naturally change as you age, and understanding this context helps us interpret your results.
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Hormone levels are typically at their most stable (though everyone is unique). Testing on day 3 gives a clear picture of ovarian function and can help identify conditions like PCOS or premature ovarian insufficiency.
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Perimenopause can begin anytime from your late 30s to late 40s. During this transition, your hormones may fluctuate significantly — even from month to month. You might notice:

Hormone testing during perimenopause can be tricky because levels vary so much. FSH levels may range from normal to elevated within the same month. If you're over 45 with classic perimenopausal symptoms, testing may not be necessary — your symptoms and medical history are often enough for your GP to assess the transition.
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However, if you're under 45 and experiencing these symptoms, testing can help determine if perimenopause has begun early.
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After menopause (12 consecutive months without a period), your FSH levels are typically consistently elevated, and oestrogen levels will be low. Testing can help support a menopause assessment if there's uncertainty, particularly after a hysterectomy or with an IUS in place.

If you're unsure whether this test is right for you or when to take it, please get in touch. We're here to help you get the most meaningful results.

Important: This information is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult your GP or an AHPRA-registered healthcare provider for advice tailored to your specific situation.