Pregnancy blood tests: before, during and after
Preconception checks, reproductive carrier screening, NIPT from ten weeks, a quantitative pregnancy blood test, and the postpartum check almost nobody is offered.
Non-invasive prenatal test (NIPT)
Screening for common chromosome conditions from 10 weeks, from a simple blood test.
Reproductive carrier screening
Find out if you carry a gene change for three common serious conditions before you conceive.
Preconception check
The checks doctors recommend before you start trying, in one visit.
Pregnancy blood test (hCG)
A quantitative pregnancy test, more sensitive than a urine test.
Postpartum recovery check
Iron, thyroid and nutrients: the things that get missed after a baby.
Genome-wide NIPT
The standard NIPT plus every other whole-chromosome change and the larger deletions and duplications, from the same blood sample.
Single-gene NIPT
Screening for a panel of serious single-gene conditions that arise new in a pregnancy and are missed by standard NIPT.
Fetal RhD test
Tells an RhD negative mother whether her baby is RhD positive, so anti-D can be targeted rather than given routinely.
Expanded carrier screening
Screening for hundreds of serious recessive and X-linked conditions you could pass on, from a saliva sample.
Expanded carrier screening, couple
Both partners screened together on the expanded panel, reported as a couple risk with genetic counselling included.
About this stage
This stage runs from the year before you try to the year after a baby arrives. Before conception it covers immunity checks, blood group and antibodies, iron studies, folate, vitamin B12, vitamin D, TSH and HbA1c, alongside reproductive carrier screening for cystic fibrosis, spinal muscular atrophy and fragile X. In pregnancy it covers hCG for confirming and tracking an early pregnancy, and NIPT from ten weeks. After birth it covers iron, thyroid including antibodies, and the nutrient markers that explain a lot of first-year exhaustion.
The questions change with the phase but they are always practical. What blood tests should I have before we start trying. Is carrier screening the same thing as NIPT. When can I have NIPT, and is it rebated. What does a high-chance result actually mean. How fast should hCG rise. Why do I still feel flattened at eight months postpartum when everyone says it is just tiredness.
Testing fits differently at each point. Preconception bloods are about fixing the fixable early, particularly iron and thyroid, and knowing your immunity status before rather than after. Carrier screening is once in a lifetime and is now recommended for every couple planning a pregnancy, regardless of family history. NIPT is a screening test with very high accuracy for the common chromosome conditions. The postpartum check exists because postpartum thyroiditis and iron deficiency are common, easily measured, and routinely put down to having a newborn.
Timing is the thing people most often get wrong. Carrier screening is best done before you conceive, because that is when the widest range of options is open to you. Preconception bloods are most useful about three months out, so low iron or an unsuspected thyroid problem can be addressed with your doctor before you start trying. A quantitative hCG can confirm a pregnancy earlier than a urine test, and it is the trend across 48 hours rather than any single number that a doctor reads.
The honest limits matter here more than anywhere. NIPT and carrier screening are screening, not diagnosis: a high-chance NIPT result screens for a condition and is followed by the offer of diagnostic testing, and a three-gene carrier panel does not cover every genetic condition. Self-pay, not Medicare-rebated, and genetic counselling is arranged where a result calls for it.
Preconception blood tests: the checklist
What is worth checking in the months before you start trying.
Reproductive carrier screening in Australia
Cost, the Medicare rebate, and three-gene versus expanded panels.
How much does NIPT cost in Australia?
The main panels compared, and what changes the price.
NIPT in Australia: cost, timing and accuracy
The ten-week rule, and what a high-chance result means.
hCG levels by week
How the pregnancy blood test is read, and why the trend matters.
Postpartum blood tests
Thyroid, iron and the six-week check that often gets skipped.
Choose your test
Pick the test that matches where you are. Each page lists every marker, the timing rules such as the ten-week point for NIPT, and the price before you order.
A doctor requests it
Upload a request your own GP, obstetrician or midwife has signed, or answer a short questionnaire and have a KnowLuna women's health doctor request it for you.
Collect and understand
Give your sample at an accredited collection centre near you, or choose a home kit or a nurse visit where the test allows it. Results are explained in plain English by a doctor, with genetic counselling arranged if a result calls for it.
Common questions
When can I have NIPT, and is it a diagnosis?
From ten weeks of pregnancy, once there is enough placental DNA in your blood to read reliably. NIPT is a screening test, not a diagnosis. It gives a very high or very low chance for the common chromosome conditions. A high-chance result is offered confirmation with a diagnostic test, and a doctor talks you through what that involves.
Is reproductive carrier screening the same as NIPT?
No. Carrier screening looks at your own genes to see whether you carry a gene change you could pass on, and is ideally done before pregnancy. NIPT looks at placental DNA circulating in your blood during pregnancy to screen the baby for chromosome conditions. Different tests, different timing, different questions.
What blood tests are typically done before conceiving?
Commonly immunity status, blood group and antibodies, a full blood count and iron studies, folate and vitamin B12, vitamin D, thyroid function and HbA1c, with carrier screening alongside. Ideally about three months before you start trying, so anything low has time to be addressed with your doctor.
I had a baby months ago and still feel awful. What gets checked?
Iron stores and a full blood count first, since pregnancy and blood loss at birth both draw on them and stores rebuild slowly. Then thyroid function with antibodies, because thyroid inflammation after birth is common and is regularly mistaken for normal new-parent exhaustion. Vitamin D, B12, folate and HbA1c round it out. A doctor reads the set together.
Sources and further reading
- RANZCOG: Prenatal screening and diagnostic testing for fetal chromosomal and genetic conditions (C-Obs 59)
- RANZCOG: Genetic carrier screening (statement C-Obs 63)
- Pregnancy, Birth and Baby: non-invasive prenatal testing (NIPT)
- Pregnancy, Birth and Baby: genetic carrier screening
- Pregnancy, Birth and Baby: planning for your pregnancy
General information only, not medical advice. A blood test is one input to a doctor's assessment, not a diagnosis on its own. If your symptoms are severe or sudden, see a doctor promptly. Read our medical disclaimer.
The same care at every point.