112 Harley Street
Coronavirus (Covid 19) Notice: For what you need to do, please read the latest Government information.
The London Women’s Clinic offers the Harmony Test from a gestation of 11 weeks.
A safe, non-invasive test that measures fetal cells present in the mother's blood to produce a 99% accurate Down Syndrome screening result and fetal sex (if requested). Because the test is non-invasive it cannot harm you nor your baby. The appointment includes an accurate dating scan and blood test with the results of the test within 7 working days. If you have already had either the nuchal scan or integrated test and have received a high risk result you may consider this test to obtain a more accurate second opinion.
The test screens for the three most common birth defects caused by chromosomal abnormality:
- Down Syndrome
- Edward's Syndrome
- Patau Syndrome
What detail is in the reports?
Our scan report will:
- Check the viability of your pregnancy
- Establish the gestational age via a series of measurements
- Confirm the number of babies
The laboratory report will show a result, risk score and recommendation for the three common chromosomal abnormalities:
- Trisomy 21 (Down Syndrome)
- Trisomy 18 (Edwards Syndrome)
- Trisomy 13 (Patau Syndrome)
A high-risk indication will be given where the result of your non-invasive prenatal test has fallen below the 1/100 threshold. If your result is 1/100 or higher risk you will be offered an invasive diagnostic test, such as a CVS or amniocentesis to give you a definite answer.
Fetal sexing in now available for both singleton and twin pregnancies:
- A male result may apply to one or both fetuses
- A female result applies to both fetuses
- X and Y aneuploidy testing is not available for twin pregnancy
How accurate is the Harmony prenatal test?
Verified clinical data from our genetics laboratory states that:
- Down Syndrome >99% (0.1% false positive rate)
- Edwards Syndrome >97% (0.1% false positive rate)
- Patau Syndrome 80% (0.1% false positive rate)
Detection and false positive rates are calculated on a risk cut-off of 1/100.
Fetal sex reporting (detection of the Y chromosome) has an accuracy of greater than 99%.
Is the Harmony prenatal test always successful?
97+% of the time yes. However, the result from every sample is subjected to a large volume of quality control checks. 3% or less will not pass this stage and in this case no result will be issued. In this event the laboratory will repeat the analysis free of charge but there will be a delay in the result being issued. In the unlikely event of a second failure, we offer an appointment with our Fetal Medicine Specialist to discuss the possible options at no additional charge.
What happens with my results?
We will call you no more than 10 days after your appointment to let you know your results and will send a report detailing your estimated risk and fetal sex (if requested).
Does the Harmony prenatal test replace my 12 week nuchal scan or a CVS/amniocentesis?
No, if you have the Harmony test before 12 weeks gestation you will still need to have a scan at 12 weeks to check your baby’s anatomy. A non-reassuring screening result following the Harmony test can only be absolutely verified by having an invasive diagnostic test such as a CVS or amniocentesis.