Preconception blood tests: the checklist before you try.
A preconception blood check usually covers rubella and varicella immunity, blood group and antibodies, iron and a full blood count, folate and B12, vitamin D, thyroid function and a glucose marker, with carrier screening as an optional add-on. Done three to six months before trying, it leaves time to act on anything it finds.
Why a preconception check matters, three to six months out
Most of the things that matter for a healthy early pregnancy are decided before you know you are pregnant. The neural tube closes in the first four weeks. Immunity to rubella cannot be topped up once you conceive. Iron stores that are already low get drawn down fast. A blood check a few months ahead gives you and your doctor time to sort these things out calmly.
Preconception care is a recognised part of Australian general practice, and the blood tests below combine the routine items in RACGP and RANZCOG preconception guidance with the risk-based checks doctors commonly add. None of them is exotic. What tends to go wrong is that they are never ordered, because many pregnancies are not planned and many women do not see a doctor until a positive test.
The checklist
Here is what a comprehensive preconception blood check includes, why each item is there, and what a result might lead to. Your doctor may add or drop items depending on your history.
| Check | Why it is tested | What a result can lead to |
|---|---|---|
| Rubella immunity | Rubella infection in early pregnancy can seriously harm the baby. Immunity from childhood vaccination can fade. | If you are not immune, vaccination before pregnancy is discussed; it cannot be given during pregnancy. |
| Varicella (chickenpox) immunity | Chickenpox in pregnancy carries risks for you and the baby. Many adults are immune without remembering the illness. | Same as rubella: a gap is fixable before conception, not after. |
| Blood group and antibodies | Your Rh (D) status and any red cell antibodies affect how your pregnancy is monitored. | If you are Rh negative, your care team plans for it during pregnancy and at birth. |
| Iron studies and full blood count | Pregnancy roughly doubles your iron need. Ferritin shows your stores; the full blood count shows whether you are anaemic now. | Low stores are corrected before pregnancy rather than chased during it. |
| Folate and vitamin B12 | Both are needed for the baby's early neural development. B12 can be low with a plant-based diet or absorption problems. | Your doctor advises on folate before conception; a low B12 is investigated. Whatever the folate result, Australian guidance is a daily folic acid supplement (400 to 500 micrograms, or the higher dose your doctor advises if you are at higher risk) from at least a month before trying, plus 150 micrograms of iodine, so a normal level does not remove the need for it. |
| Vitamin D | Often low in Australian women despite the sun, and important for bone health in pregnancy. Sufficient is generally 50 nmol/L or above. | Your doctor discusses how to correct a low level. |
| Thyroid (TSH) | Thyroid hormone drives the baby's brain development in the first trimester, before its own thyroid works. Thyroid problems are common in women of reproductive age. | An abnormal TSH is followed up before conception, when it is easiest to manage. |
| Glucose (HbA1c) | Undiagnosed diabetes or pre-diabetes raises risks in early pregnancy. HbA1c reflects your average glucose over about three months. | A raised result is investigated and managed before trying. |
Ranges vary by laboratory; your report shows the range your lab uses. Typical ranges on this page are drawn from Pathology Tests Explained (RCPA) and the sources listed below.
Australian preconception and antenatal guidance also includes a set of routine infection screens, which KnowLuna does not offer and your GP arranges as part of standard care, along with tests for inherited blood conditions common in some family backgrounds. Those are conversations to have with your own doctor.
Carrier screening as the optional add-on
The checklist above looks at your health. Reproductive carrier screening looks at your genes, specifically whether you carry a change linked to cystic fibrosis, spinal muscular atrophy or fragile X syndrome. Carriers are usually healthy and often have no family history, which is why RANZCOG recommends it is offered to everyone planning a pregnancy. A fragile X premutation is the exception, because it can affect the carrier's own health, and a genetic counsellor covers that.
It is optional, and the best time to do it is now, before conception, when results (which take two to three weeks) arrive with every option still open. If you are a carrier of cystic fibrosis or spinal muscular atrophy, your partner is tested next. Read more in carrier screening cost in Australia.
What Medicare covers with a GP, and what KnowLuna offers self-pay
Every test on the checklist can be requested by your GP, and most of the items attract a Medicare rebate when your GP requests them. Two do not always: vitamin D testing is rebated only if you meet specific criteria, and HbA1c screening only if you are at higher risk of diabetes, so those two may cost extra even through a GP. Many laboratories bulk-bill the rebated items, so the out-of-pocket cost through a GP can be small or nothing. The 3-gene carrier screen has also been rebated through a GP since November 2023. If cost is your main concern, your GP is the right first stop, and we say so plainly.
KnowLuna's preconception check is self-pay and is not rebated by Medicare. It bundles the whole checklist into one collection at an accredited (NATA/RCPA) centre near you, at a time you choose, with a plain-English report in your account. Option 1 is $299 with a signed request from your own doctor. Option 2 is $379: a KnowLuna women's health doctor requests the panel and explains every result in a 20-minute video consult. Anything abnormal is always followed up by a doctor.
Partner tests
Preconception is not only about you. If you have been trying for a while, or simply want the full picture from the start, a semen analysis is the single most informative male fertility test, and roughly half of all fertility difficulty involves a male factor. If you are a carrier of cystic fibrosis or spinal muscular atrophy, your partner's carrier test is the next step. Partners planning a pregnancy are also usually advised to check their own vaccination status, which their GP can do.
Reading your results and what to do before trying
Most preconception results are reassuring, and that is genuinely useful: it means you can stop wondering. Where something needs attention, it usually falls into one of a few groups.
- An immunity gap. Your doctor talks you through vaccination and the interval to wait before conceiving.
- Low iron, folate, B12 or vitamin D. Your doctor explains how to bring the level up and when to recheck.
- An abnormal thyroid or glucose result. These are followed up and managed before pregnancy, and monitored during it.
- A carrier result. Partner testing and genetic counselling follow; the result itself is a chance, not a diagnosis.
- Blood group findings. Nothing to do now; your antenatal team uses the information later.
Keep a copy of every result. Your antenatal care provider will want your blood group and rubella status at the first visit, and will arrange the routine infection screening then if it has not been done. If you are also using the AMH and fertility panel to understand your ovarian reserve, the two sets of results are best read together.
Common questions
What blood tests are typically done before conception?
Rubella and varicella immunity, blood group and antibodies, iron studies and a full blood count, folate and vitamin B12, vitamin D, thyroid function (TSH) and a glucose marker such as HbA1c, plus routine infection screening arranged through your GP. Reproductive carrier screening for cystic fibrosis, spinal muscular atrophy and fragile X is offered as an optional addition.
Should I have a blood test before getting pregnant?
RANZCOG and RACGP guidance recommends preconception care, and blood tests are a core part of it, because several findings (immunity gaps, low iron, thyroid problems, undiagnosed diabetes) are far easier to address before pregnancy than during it. Three to six months before trying is the ideal window, but any time before conception is useful.
Is preconception genetic testing available in Australia?
Yes. The 3-gene carrier screen is widely available through GPs, with a Medicare rebate since November 2023, and through self-pay services such as KnowLuna. Expanded panels covering hundreds of genes are available self-pay. All are screening tests that describe chance, and a positive carrier result is followed by partner testing and genetic counselling.
Do I need to fast for preconception blood tests?
No. Nothing on the standard checklist requires fasting, including HbA1c, which measures average glucose over about three months. If your doctor adds a fasting glucose or fasting lipid test, the collection centre will tell you. Otherwise, come at a time that suits you and drink water as normal.
Is reproductive carrier screening the same as NIPT?
No. Carrier screening tests you (and if needed your partner) before or early in pregnancy for gene changes you could pass on. NIPT tests your blood from 10 weeks of pregnancy to screen the baby for chromosome conditions such as Down syndrome. They answer different questions at different times.
Sources and further reading
- RANZCOG: Pre-pregnancy counselling (C-Obs 3a)
- RACGP: Guidelines for preventive activities in general practice (the Red Book)
- Pregnancy, Birth and Baby: planning for your pregnancy
- Pregnancy, Birth and Baby: preconception health for females
- Pregnancy, Birth and Baby: genetic carrier screening
- NHMRC Nutrient Reference Values: folate
General information only, not medical advice. If your symptoms are severe or sudden, see a doctor promptly. This page does not replace a consultation with a doctor who knows your history; read our medical disclaimer.