FAQs - Section 6: Requesting Harmony
We recommend that the test be done between 10 and 14 weeks gestation.
The Harmony Prenatal Test relies on there being sufficient fetal DNA in the maternal circulation for analysis. The concentration of fetal DNA rises during pregnancy. The particular time at which the fetal DNA concentration is high enough for detection will vary from woman to woman.
In practice, Harmony should not be offered to women at less than 10 weeks gestation. More than 95% of women will have sufficient fetal DNA for analysis after this gestation. Harmony has not been validated at an earlier gestation.
The fetal DNA concentration rises slowly between 10-20 weeks of gestation. Deferring Harmony for 1-2 weeks may reduce the chance of the woman having an undetectable fetal DNA.
Harmony can be performed at any time after the 10th week of pregnancy. However, the usefulness of information obtained after 20 weeks may be limited by other factors such as the intervention options available at later gestations.
The laboratory needs to have accurate information about gestation and the presence of twins so that the Harmony test can be reported. Thus we recommend that an antenatal scan to confirm gestational age, viability, and number of fetuses be done before the Harmony test is ordered.
The decision about which date is more likely to be correct must be resolved by the doctor responsible for managing the pregnancy. Harmony does not provide any information regarding this.
If a woman has different estimated dates for delivery, it may be preferable to defer Harmony until a gestation of 10 weeks calculated according to the later date. In other words, it is usually preferable to err on the side of taking a sample for Harmony later rather than earlier.
We require a special request form to ensure that we obtain the required information to interpret the analytical result correctly. The Harmony Prenatal Test will not be performed unless the special request form is received and signed by the referring doctor and the patient (two signatures are required).
The following healthcare practitioners can request Harmony:
- A medical practitioner who is accountable for the care provided to a pregnant woman; and
- A midwife or other allied health professional working as part of the team environment in which a doctor has overall accountability for the care provided to an individual patient.
There is no legal restriction on who can order or provide Harmony. Some providers make Harmony available without any involvement of a healthcare professional or accreditation of the laboratory providing the test.
Sonic Genetics provides medical tests to assist healthcare professionals and their patients achieve better health outcomes. Harmony is an important test that carries significant implications for the patient and her baby. Our policy is to support clinicians who are accountable for the care provided to pregnant women. We do not accept test requests from patients themselves, or from clinicians who are not responsible for the woman’s care.
Our laboratories are accredited by a national regulatory agency to provide these tests, and we are bound by the requirements of our accreditation. With regard to genetic tests, the standards required by the regulatory agency currently limit the provision of genetic tests to the context of a medical consultation. This requirement prevents us from accepting Harmony requests from non-medical healthcare professionals such as independent practising midwives and genetic counsellors.
We encourage independent non-medical healthcare professionals to develop a suitable relationship with a medical practitioner to facilitate the inclusion of Harmony in a patient’s care.
When the patient has a completed test request form, she is directed to call Sonic Genetics on 1800 010 447 to nominate a convenient collection centre, to arrange a time for collection, and to pay for the test.
Sonic has 1,850 collection centres nationally, but not all of these are currently resourced to collect this test. For this reason, we ask that each patient identify the most convenient collection centre that collects Harmony and book a time.
We have limited the number of collections centres for Harmony because we need a quick and smooth transport link to get the samples to the laboratory. The DNA in maternal blood degrades rapidly, and the need for prompt transport also limits the days or times that samples can be collected. We will be expanding this network to cover most of our collection centres nationally.
When the patient arrives at the designated collection centre, the details on her request form will be confirmed and a sample of blood collected into special tubes. This process takes approximately 20 minutes.
Please note: the sample for Harmony should not be collected through the same needle as other blood tests. The Harmony test is exquisitely sensitive and we make this restriction to reduce the risk of contaminating the sample.
There is no need for the patient to fast, avoid specific medications, or avoid intercourse.
Tests can be cancelled by ringing us on 1800 010 447. If the test has not been completed, the test process will be cease and no result issued.
If the test has been completed, we are obliged to issue the report to the requesting clinician who is then responsible for the further management of the report.
Depending on the stage at which the test is cancelled, the payment for Harmony may be refunded; this is at the discretion of the laboratory as costs may have already been incurred.