For many expectant parents in Hong Kong, choosing the right Hong Kong Down’s Syndrome Test is one of the most important steps during pregnancy. From the traditional OSCAR screening in public hospitals to modern NIPT options like NIFTY and SafeT21, Hong Kong offers several approaches to prenatal chromosomal screening.
In Hong Kong, three main options are commonly discussed: the OSCAR test, which is widely available in the public healthcare system, and two non-invasive prenatal testing (NIPT) choices, NIFTY and SafeT21, which are offered in private clinics. While all three tests share the same goal—assessing risk for chromosomal conditions—their methods, accuracy, costs, and implications differ significantly. Understanding these differences can help parents choose the test that best suits their needs, budget, and peace of mind.
What is OSCAR?
OSCAR stands for One-Stop Clinic for Assessment of Risk. It is a first-trimester screening test typically carried out between the 11th and 13th weeks of pregnancy. The process combines a maternal blood test with an ultrasound scan, particularly focusing on the nuchal translucency (NT), which is the fluid-filled space at the back of the baby’s neck. Together with the mother’s age and medical history, these results are analyzed using statistical models to provide a risk ratio for Down syndrome and other chromosomal conditions.
The OSCAR test has been in use for many years in Hong Kong and worldwide. In the local public healthcare system, it is often the first-line screening option provided to pregnant women. In private clinics, OSCAR is also available at a relatively affordable cost, usually ranging from HK$1,000 to HK$2,000.
While OSCAR is helpful, it is important to note that it does not directly test fetal DNA. Its accuracy for trisomy 21 detection is around 85 to 90 percent, which means that false positives are relatively common. In practice, this can cause unnecessary anxiety for parents, as high-risk OSCAR results often lead to recommendations for further testing, sometimes involving invasive procedures such as amniocentesis or chorionic villus sampling (CVS), which carry a small risk of miscarriage.
The Rise of NIPT in Hong Kong
In recent years, non-invasive prenatal testing (NIPT) has rapidly grown in popularity in Hong Kong. Unlike OSCAR, NIPT analyzes cell-free fetal DNA (cfDNA) that circulates in the mother’s bloodstream. This DNA originates from the placenta and can be detected as early as the 10th week of pregnancy. By sequencing and analyzing these DNA fragments, NIPT provides a far more direct and accurate assessment of chromosomal abnormalities.
A key advantage of NIPT is its very high accuracy. Studies consistently show that NIPT has a sensitivity and specificity of over 99 percent for trisomy 21, with similarly strong results for trisomy 18 and 13. The false-positive rate is also much lower than OSCAR, which reduces the likelihood of unnecessary invasive follow-up procedures.
In Hong Kong, two NIPT options dominate the private market: NIFTY, developed by BGI (Beijing Genomics Institute), and SafeT21, developed by the Chinese University of Hong Kong (CUHK).
NIFTY: International Reach and Broad Coverage
NIFTY is one of the world’s most widely used NIPT platforms, with millions of tests conducted globally. It is available in many Hong Kong private clinics and can be performed from the 10th week of pregnancy onward.
NIFTY screens for the three major trisomies (T21, T18, and T13), as well as sex chromosome abnormalities. More advanced versions, such as NIFTY Plus, also screen for over 20 additional microdeletion and duplication syndromes, making it one of the most comprehensive options available.
In terms of accuracy, NIFTY boasts greater than 99 percent sensitivity and specificity for Down syndrome. However, results usually take a little longer because the analysis is often performed outside Hong Kong, typically requiring 7 to 10 working days. Costs range from HK$4,000 to HK$6,000, depending on the clinic and whether expanded panels are included.
For parents who want internationally recognized technology and the broadest possible screening coverage, NIFTY remains a trusted choice.
SafeT21: A Hong Kong Innovation
SafeT21 is another highly regarded NIPT option, but unlike NIFTY, it was developed by the Chinese University of Hong Kong (CUHK) and is conducted in local laboratories. This makes it a distinctly Hong Kong innovation and an option that appeals to parents who value local medical research and faster turnaround times.
SafeT21 focuses on the key conditions: trisomy 21, 18, and 13, as well as sex chromosome abnormalities. While it does not cover as many microdeletions as NIFTY Plus, it delivers comparable accuracy for the core trisomies, with sensitivity and specificity of over 99 percent.
Because the testing is processed locally, results are typically available within 3 to 5 working days, significantly faster than NIFTY. Costs are also slightly lower, averaging HK$4,000 to HK$5,000.
For parents who want quick results and confidence in a test rooted in Hong Kong’s own medical research, SafeT21 is a strong contender.
Choosing Between OSCAR, NIFTY, and SafeT21
Deciding which test is best depends on several factors, including maternal age, pregnancy history, risk level, budget, and how quickly results are needed.
For women considered at lower risk, OSCAR may be an acceptable starting point, particularly if using the public healthcare system. It remains cost-effective and can identify some structural abnormalities through ultrasound, though parents must be prepared for a higher chance of false positives.
For high-risk pregnancies, such as women over 35, those with a family history of chromosomal abnormalities, or those who have had concerning ultrasound findings, NIPT is generally recommended due to its higher accuracy and lower false-positive rate. Within the NIPT options, parents who value the broadest coverage and international validation often choose NIFTY, while those who prefer a locally based test with quicker turnaround times are drawn to SafeT21.
It is also worth noting that some parents choose to undergo both OSCAR and NIPT—using OSCAR for its ultrasound insights and NIPT for its DNA-based accuracy. While this dual approach provides maximum reassurance, it may not be necessary in every case and should be discussed with a healthcare provider.
Conclusion
Prenatal screening is a crucial step for parents-to-be in Hong Kong, offering early insights into their baby’s health and helping guide decisions during pregnancy. OSCAR, as the traditional first-trimester screening available in public hospitals, remains a widely used option but has limitations in accuracy. NIPT options such as NIFTY and SafeT21 provide far greater accuracy and reassurance, with NIFTY standing out for its global validation and broad screening, and SafeT21 offering the advantages of faster results and a strong local research foundation.
Ultimately, the choice between OSCAR, NIFTY, and SafeT21 depends on personal circumstances, priorities, and the advice of an obstetrician. By weighing the strengths and limitations of each test, expectant parents can make a decision that supports both their peace of mind and the health of their pregnancy.