PARENTS

BabySafe
Non-Invasive Prenatal Testing

BabySafe NIPT detects genetic disorders of the fetus as early as 10 weeks of pregnancy, using Next Generation Sequencing technology that is highly sensitive and specific.

UNDERSTANDING NIPT

What is Non-Invasive Prenatal Testing (NIPT)?

BabySafe NIPT is a prenatal screening test during pregnancy to identify the risk of the baby for having certain birth defects or genetic conditions.

During pregnancy, DNA is released from the placental cells of the fetus and being circulated freely in the mother’s bloodstream along with the maternal cell-free DNA (cfDNA).

This test method examines the cfDNA isolated from the maternal blood sample and identify the DNA fragments that are derived from the fetus. The percentage of fetal cfDNA in the maternal blood, which is known as the fetal fraction, is generally at the range of 3-30%, depending on the gestational age, maternal weight, and mother’s health conditions. By determining the genetic sequence of the fetal cfDNA, the test is able to identify any missing or extra genetic materials that may lead to certain birth defects or genetic conditions.

TIMEFRAME

When should
you test?

The test can be done as early as 10 weeks of pregnancy. However, to detect microdeletion/ microduplication which spans a smaller fragment of the DNA, it is recommended to test after 13 weeks of pregnancy to achieve the higher fetal fraction (%) required for better accuracy.

SCREENING

How is BabySafe NIPT
done?

This is a non-invasive test method where only blood sample is required, unlike the invasive procedures such as amniocentesis or chorionic villus sampling. Blood sample (10mL) is collected into a specially designed cfDNA blood collection tube which contains stabilizing solution to maintain the integrity of cfDNA.

SERVICES

Which screening tests are offered?

For singleton pregnancy, we are able to screen for 22 types of fetal chromosomal aneuploidy, sex chromosome aneuploidies and up to 60 microdeletion/microduplication syndromes. For twin pregnancy, only 22 types of fetal chromosomal aneuploidy and sex chromosome aneuploidies are screened. 

Babies with Down syndrome have three copies of chromosome 21 and have intellectual disabilities that range from mild to severe. Children with Down syndrome will need extra medical care depending on the child’s specific health problems. Early intervention has allowed many individuals with Down syndrome to lead healthy and productive lives. The presence of medical conditions, like heart defects, can affect the lifespan in these children and adults; however, most individuals with Down syndrome will live into their 60s. Miscarriage occurs in about 30% of pregnancies with Down syndrome while overall about 1 in 700 babies are born with Down syndrome.

Babies with trisomy 18 have three copies of chromosome 18 and have severe intellectual disabilities and birth defects typically involving the heart, brain, and kidneys. Babies with trisomy 18 can also have visible birth defects such as an opening in the lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate), a small head, clubbed feet, underdeveloped fingers, and toes, and a small jaw. Unfortunately, most pregnancies with trisomy 18 will miscarry. If born alive, most affected babies with trisomy 18 will pass away within the first few weeks of life. About 10 percent survive to their first birthday. Trisomy 18 occurs in approximately 1 in 3,000 live births.

Babies with trisomy 13 have three copies of chromosome 13 and have severe intellectual disabilities. They often have birth defects involving the heart, brain, and kidneys. Visible abnormalities include extra fingers and/or toes or an opening in the lip, with or without an opening in the palate. Given the severe disabilities, most pregnancies affected by trisomy 13 will miscarry. If born alive, most affected babies with trisomy 13 will pass away within the first few weeks of life. About 10 percent survive to their first birthday. Trisomy 13 occurs in approximately 1 in 5,000 live births.

Babies with monosomy X are biological females who have one X chromosome instead of two. Unfortunately, a high proportion of pregnancies with monosomy X will result in a miscarriage in the first or second trimester of pregnancy. Babies with monosomy X that make it to term may have heart defects, learning difficulties, and infertility. In most cases, babies with monosomy X will need extra medical care including hormone therapy at various stages of life.

Babies with XXY syndrome have two X chromosomes and one Y chromosome (XXY). This condition can be associated with learning difficulties and behavioral problems. People with Klinefelter syndrome might be infertile. About 1 in 500 biological males will be born with Klinefelter syndrome.

Babies with Triple X syndrome have three X chromosomes (XXX). Children with this condition could be taller than average and might experience learning difficulties or behavioral problems. Approximately 1 in 800 biological females will be born with three X chromosomes.

Babies with XYY syndrome have one X chromosome and two Y chromosomes (XYY). Most babies with XYY syndrome do not have any birth defects. Children with XYY could be taller than average and have an increased chance for learning, speech, and behavioral problems. Approximately 1 in 1,000 biological males will be born with one X chromosome and two Y chromosomes.

A missing piece of chromosome 5 causes Cri-du-chat syndrome, also called 5p- (5p minus) syndrome. The name “Cri-du-chat” was given to this syndrome due to the high-pitched, cat-like cry that babies with this syndrome often make. Babies with Cri-du-chat syndrome typically have low birth weight, a small head size, and weak muscle tone. Feeding and breathing problems are common in infancy. Children with this disorder have moderate-to-severe intellectual disability, including speech and language delays. They may also have growth delays, behavior problems, and some have curvature of the spine (scoliosis). About one in every 20,000 babies is born with Cri-du-chat syndrome. They may also have heart defects, growth delay, behavior problems and some have curvature of the spine.

22q11.2 deletion syndrome, also called DiGeorge syndrome or Velo-Cardio-Facial syndrome (VCFS), is caused by a missing piece of chromosome number 22. About one in every 2,000 babies is born with 22q11.2 deletion syndrome. The majority of children with this disorder have heart defects, immune system problems, and specific facial features. Most children with 22q.11.2 deletion syndrome have mild-to-moderate intellectual disability and speech delays; some will also have low calcium levels, kidney problems, feeding problems, and/or seizures. About one in five children with 22q11.2 deletion syndrome have autism spectrum disorder; 1 in 4 adults with 22q11.2 deletion syndrome have a psychiatric illness, like schizophrenia.

Prader-Willi syndrome occurs when either a small piece of chromosome 15 is missing or when both copies of chromosome 15 come from the same parent (called uniparental disomy, or UPD). Babies with Prader-Willi syndrome have low muscle tone and problems with growth and feeding. Children with Prader-Willi syndrome have delayed milestones, short stature, rapid weight gain leading to obesity, and intellectual disability. About 1 in 10,000 babies are born with Prader-Willi syndrome. 

Angelman syndrome happens when either a small piece of chromosome 15 is missing, or when both copies of chromosome 15 come from the same parent (called uniparental disomy, or UPD). About 1 in 12,000 babies are born with Angelman syndrome. Babies and children with Angelman syndrome have severe intellectual disability, delayed milestones, seizures, and problems with balance and walking. 

1p36 deletion syndrome, also referred to as Monosomy 1p36 syndrome is caused by a missing piece of chromosome 1. Children with 1p36 deletion syndrome have intellectual disabilities. Most have heart defects and weak muscle tone. About half of affected individuals have seizures (epilepsy), behavioral problems, and hearing loss. Some children with 1p36 deletion syndrome also have vision problems or additional birth defects of other organs. About 1 in 5,000 newborn babies has 1p36 deletion syndrome.

FAST TURNAROUND TIME

When are the
results ready?

The results are ready within 5-7 working days after the laboratory receives your blood sample.

UNDERSTANDING THE RESULTS

What does the result mean?

A low-risk test result indicates that the fetus has a low risk of developing the target disease of this screening.

A high-risk test result indicates that the fetus has a high risk of developing the target disease of this screening. However, as a screening test, genetic counselling and invasive prenatal diagnosis are needed after an initial high-risk result.

If a high risk of microdeletion/microduplication syndrome is detected, prenatal diagnosis is recommended to be combined with maternal chromosome analysis to exclude maternal influence.

Contact your clinicians to interpret the results and guidance for clinical management

MUST READ

How do lab sciences work?

As a non-invasive method, NIPT acts as a screening test and if there is any high-risk result, an invasive confirmatory test is required. The possibility of other abnormalities not screened in this test cannot be excluded, and systematic ultrasound examinations and other prenatal examinations should be conducted.

Despite the use of the best technology available, NIPT results may have variable interpretation occasionally. This is due to the physiological differences between pregnant women, which are not limited to:

  1. Low gestational age
  2. Maternal Obesity and high BMI
  3. In vitro fertilization (IVF) fetuses
  4. Placental dysfunction and hypertensive disease in pregnancy
  5. Specimen-related issues leading to degradation of DNA and data fluctuation
  6. Early loss of a twin
  7. Maternal diseases or severe immune maternal disorders

It is important to highlight that to detect microdeletion/microduplication, which is a minute defect at the molecular level, a much higher fetal fractions are required. On rare occasions, some of the microdeletion may be unreportable due to low fetal fraction leading to low data for analysis. However, the results for Down, Edward and Patau syndromes, which are the 3 most common fetal anomalies will be provided.

FIND OUT MORE

Support for
Parents

As part of our commitment to help parents to further understand the diseases, we provide genetic counselling services by experienced genetic counsellors. If you would like to know more about our services, please reach out to us. Prenatal screening tests during pregnancy can identify the risk of your baby for having certain birth defects, 

Contact Us

Sources for
Parents

Aneuploidy is a condition of having missing or extra chromosomes. The risk of having a child with an aneuploidy increases as a woman ages. The most common aneuploidy is trisomies, which represent about 0.3% of all live births. Trisomy indicates for presence of extra chromosome, which includes Down syndrome (trisomy 21), Patau syndrome (trisomy 13) and Edwards syndrome (trisomy 18). Another type of aneuploidy is Monosomy, which there is a missing of chromosome. For example, Turner syndrome, a condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing.

Microdeletion and microduplication syndromes are defined as a group of clinically recognisable disorders characterised by sub microscopic deletions or duplications of contiguous genes on particular parts of chromosomes and each potentially contributing to the phenotype independently. Individuals with microdeletions or microduplication syndromes are usually associated with intellectual disability (ID) and developmental delay (DD), for instance: 15q11-q13 deletion associated with Prader–Willi and Angelman syndromes, 22q11 deletion associated with DiGeorge Syndrome and 1q21.1 microduplication that associated with 1q21.1 microduplication syndrome