Reproductive carrier screening

Reproductive carrier screening looks at three genes to see whether you carry a change you could pass on: cystic fibrosis, spinal muscular atrophy and fragile X. It is offered to everyone planning a pregnancy, because most carriers are healthy and have no family history. Through KnowLuna it is priced at launch, once our laboratory agreement is signed; waitlist members see the price first. Either pathway applies: bring your own doctor's signed request, or have a KnowLuna doctor request it and explain the result in a 20-minute video consult.

What it measures

• Cystic fibrosis (CFTR): a condition affecting the lungs and digestion. It is inherited in an autosomal recessive way, which means a child is affected only if both parents pass on a changed copy of the gene.
• Spinal muscular atrophy (SMN1): a condition affecting the nerves that control muscle movement, also autosomal recessive. The test counts copies of the SMN1 gene, since carriers usually have only one working copy.
• Fragile X (FMR1): the most common inherited cause of intellectual disability. It sits on the X chromosome and is carried through the mother's side, so the inheritance pattern is different from the other two. The test measures the length of a repeated section of the gene.

Who it's for

Anyone planning a pregnancy or early in one, with or without a family history. RANZCOG guidance is that this information should be offered to every couple, not only to those with a known risk, because most people who carry a gene change have no idea and no affected relatives. It suits women who want the result before conceiving, couples doing preconception planning together, and anyone about to start fertility treatment. It is for adults aged 18 and over. Your partner can be tested if you are found to be a carrier.

What you'll learn, and what you won't

You'll learn whether you carry a gene change for any of the three conditions screened. Being a carrier does not affect your own health for cystic fibrosis or spinal muscular atrophy, and it does not mean a child will be affected. What it does is tell you and your doctor whether the next step, testing your partner, is worth taking.

What it cannot do: a three-gene screen does not cover every genetic condition, and no screen does. It cannot rule out all inherited conditions, it does not test your baby, and a low-chance result is a reduced chance rather than a guarantee. It is also not a fertility test. A screening test is one input to a doctor's assessment, not a diagnosis on its own.

Three genes or an expanded panel?

Two approaches are available in Australia and both are reasonable. The three-gene screen covers the conditions that are most common and best understood, and it is the one written into RANZCOG guidance and the Medicare rebate. Expanded panels look at hundreds of genes at once, cost considerably more and are not rebated.

The trade-off is real. A larger panel finds more carriers, including conditions that are very rare or very variable, and it also returns more results whose meaning is uncertain, which can be unsettling and sometimes leads to further testing that changes nothing. A smaller panel is clearer to act on but covers less ground.

KnowLuna offers both. This page is the three-gene screen. The expanded carrier screening panel (300 or more genes, saliva kit at home) and the couple version, which screens both partners together and reports a shared risk, are listed with pricing on launch. Our questionnaire asks about family history, ancestry and whether you are already pregnant, and a KnowLuna doctor recommends which fits you; where you are eligible for the Medicare-rebated three-gene screen we say so before you pay for anything.

Medicare rebate through a GP, or self-pay here

Since November 2023 a Medicare rebate has been available in Australia for the three-gene reproductive carrier screen, once in a lifetime, when it is requested for reproductive planning. That rebate applies when your own GP or specialist requests the test on a Medicare-eligible request form (item 73451), and partner testing for cystic fibrosis or spinal muscular atrophy has its own item (73452).

Ordering through KnowLuna is self-pay and is not Medicare-rebated today. From launch, if you are eligible for the rebated screen, a KnowLuna doctor can request it on a Medicare-eligible form and the laboratory bulk-bills the test itself; you pay only for the doctor and the report, and we tell you the amount before you order. What you get for that is speed and explanation: no wait for a GP appointment, a doctor who requests it if you do not have a signed request, and a plain-English result with a consult to talk it through. If cost matters more than time, see your GP and use the rebate; we would rather tell you that than have you pay twice. Either way, the laboratory test itself is the same accredited test.

If you are a carrier

Most people who screen positive are healthy carriers. For cystic fibrosis and spinal muscular atrophy the result on its own changes nothing about their own health; a fragile X premutation is the exception. What happens next depends on which gene is involved.

• Cystic fibrosis or spinal muscular atrophy: your partner is tested for the same gene. If your partner is not a carrier, the chance of an affected child is very low. If both of you carry a change, there is a one in four chance in each pregnancy that a child is affected, and a genetic counsellor explains the options available before and during pregnancy.
• Fragile X: because the gene sits on the X chromosome, partner testing is not the next step. Instead a genetic counsellor explains what the length of the repeated section means, what the chance is of it expanding when it is passed on, and what testing is available in a pregnancy. A premutation can also affect your own health: about one in five women who carry one have early menopause, and carriers have a later-life chance of a tremor and balance condition, which the counsellor covers with you.
• Either way: KnowLuna arranges genetic counselling for results that need it, and your doctor stays involved. Nothing about a carrier result requires an immediate decision.

Reference ranges and what they mean

Genetic screening does not report a number against a range. Results are qualitative and are reported in one of two ways.

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.

Genetic reports are qualitative. Your report describes the genes tested, the method used and the limits of the screen.

When to do this test

Any time, ideally before you conceive. Doing it before pregnancy gives you the widest set of options and no time pressure. It is still worth doing early in a pregnancy, where the timeline is tighter but options remain. There is no fasting, no cycle timing and nothing to prepare: it is a single sample, usually a home swab or saliva kit posted to you, or a collection at an accredited centre or a nurse home visit if you prefer. It is usually a once-in-a-lifetime test, because your genes do not change. A result from a previous pregnancy usually still stands, provided it covered the same genes to the same standard, and a new reproductive partner needs their own result. Bring or upload any previous carrier screening result and a doctor confirms whether it needs repeating. If you are found to be a carrier of cystic fibrosis or spinal muscular atrophy, your partner can be tested next.

How it works

• Order online. Either upload the request your own doctor has signed, or a KnowLuna women's health doctor reviews your short questionnaire and requests the screen.
• Collect the way that suits you: a home swab or saliva kit posted to you (included), an accredited centre near you, or a nurse home visit (options below). One collection, no fasting, no timing rules.
• Genomic results take longer than routine pathology, usually a few weeks. Your report is explained in plain English in your account, with a doctor consult if you chose that option, and genetic counselling arranged where a result calls for it.

Choose how you collect

Every option is the same accredited test and the same report. Pick what suits you at checkout; the fee, if any, is added to either pathway price.

Common questions

Sources and further reading

• Pathology Tests Explained (RCPA): reproductive carrier screening
• RANZCOG: Genetic carrier screening (statement C-Obs 63)
• Medicare Benefits Schedule: item 73451, reproductive carrier screening (CF, SMA, fragile X)
• Medicare Benefits Schedule: item 73452, reproductive partner carrier testing
• Pregnancy, Birth and Baby: genetic carrier screening
• Pregnancy, Birth and Baby: genetic counselling

General information only, not medical advice. A test result is one input to a doctor's assessment, not a diagnosis on its own, and every abnormal result is followed up by a KnowLuna doctor. If your symptoms are severe or sudden, see a doctor promptly. Read our medical disclaimer.

Related

• All pregnancy tests
• Preconception check
• NIPT
• Carrier screening explained
• Carrier screening cost and the Medicare rebate
• The preconception blood test checklist