Your baby’s finally here! Here are the screening tests your little one will now need.
WORDS CHRISTEL GERALYN GOMES
While you’re likely to have been through a gamut of tests and checks during your pregnancy, there are certain things your obstetricians and gynaecologists can only find out after the baby is born. There are a number of routine procedures and tests that are necessary to check on baby’s health, once he takes that first gulp of air. These tests are meant to help in the early detection of congenital or inherited conditions that are not apparent at birth or during your pregnancy.
The tests that are administered after birth vary depending on the country you’re in, as they are based on conditions that are prevalent locally. “For example, screening for cystic fibrosis and sickle cell disease are not routinely done in Singapore as these conditions are not prevalent locally,” says Dr Justin Tan Hung Tiong, consultant paediatrician and paediatric rheumatologist at Kinder Clinic, Mount Elizabeth Novena. Here are the tests offered in Singapore.
Testing for Thyroid Problems
According to Dr Natalie Epton, paediatrician and neonatologist at Mount Elizabeth Novena Hospital, first, blood will be taken from your baby’s umbilical cord to test his or her thyroid function.
The thyroid is a butterfly-shaped gland at the base of the neck. Its main function is to produce and release hormones that regulate metabolism as well as other vital body functions like breathing, heart rate, menstrual cycles and cholesterol levels, among other things.
The cord blood test that is done right after birth will detect if your child may have an underactive thyroid gland, a condition also known as “Congenital Hyperthyroidism” (CH). “CH occurs in around one in every 3,000 live births here in Singapore. It can be associated with poor feeding and slow weight gain, but more importantly, if left undetected and untreated, can result in mental retardation,” says Dr Epton.
Besides testing for Thyroid issues, the blood that’s taken from your baby’s umbilical cord will also be used to test for blood type. “This is important for your baby's doctor to know, as your baby may be at risk of more severe jaundice if his blood type is different to yours,” says Dr Epton.
Your newborn may also have jaundice if he or she has what is called a “Glucose-6-phosphate dehydrogenase (G6PD) deficiency”. Dr Tan explains that G6PD is the enzyme that is essential for preventing oxidative damage to red blood cells. “If deficient, red blood cells lacking G6PD are susceptible to damage resulting in the breakdown of red blood cells (hemolysis). Hemolysis may result in jaundice (yellow discoloration of skin and eye) and anaemia (low red blood cell counts),” he says.
G6PD deficiency is genetically inherited, is a lifelong condition and affects male babies more than female. “Newborns with G6PD deficiency are at higher risk of developing neonatal jaundice (NNJ), which may be more prolonged and severe, especially during their first two weeks of life. This group of newborns need close monitoring of their jaundice levels as severe or untreated jaundice may lead to significant brain injury, says Dr Tan.
If your child is found to have the condition, expect that he or she will have to avoid certain foods, such as fava beans; medications such as antimalarial and some antibiotics; and environmental chemicals such as mothballs. “These substances may trigger hemolysis resulting in anaemia (low red blood cells) and jaundice,” adds Dr Tan.
“G6PD deficiency occurs in approximately 4 per cent of Chinese babies, 3 per cent of Malay babies and 1 per cent of Indian babies born in Singapore. It is much less common in Caucasians, except for those from some Mediterranean countries,” adds Dr Epton.
Testing for Hearing Impairment
Soon after birth, your child will be tested for hearing issues. “Congenital hearing loss occurs in up to one per thousand babies born in Singapore. If undetected, this can lead to speech and language delay, and educational difficulties. The earlier a hearing loss is detected, the more quickly treatment can be initiated, resulting in improving outcomes for the child,” explains Dr Epton.
Newborn hearing loss can be hereditary, but Dr Tan tells us that it can also be attributed to non-hereditary causes such as infection, injury, prematurity or can be drug-induced.
The tests your child will receive will either be the Otoacoustic Emission (OAE) test or the Auditory Brainstem Auditory Evoked Response (ABAER) test, both of which, according to
Dr Tan, are universal screening tests conducted in most hospitals in Singapore before discharge for early detection of hearing loss in a newborn. “The choice of test may vary according to each hospital’s practice,” he says.
How the tests work
In the OAE test, “a small ear probe is placed at the ear opening to detect sound produced by the vibration of outer hair cells after the cochlear is stimulated by sound. OAE can also detect blockage in the outer ear canal in the presence of middle ear fluid or damage to the outer hair cells in the cochlear,” says Dr Tan.
In the ABAER test, on the other hand, “three jelly tab sensors are applied to baby’s head to detect the brain responses evoked by clicking sounds produced by a soft earphone.”
Even if your child’s hearing tests come back normal, Dr Tan encourages parents to stay vigilant and monitor your child’s response to sounds as hearing impairment may develop gradually in some babies.
Testing for Metabolic Disorders and Enzyme Deficiencies
The Metabolic Screening Test or Inborn of Error Metabolism (IEM) Screening Test is designed to detect any difficulties your baby may have with digesting fats, proteins and sugars in milk.
This condition is an inherited one and is due to defects in genes that code for enzymes, which help the conversion of fats, proteins and sugars into usable nutrition. Without working enzymes to break down these fats, proteins and sugars into the building blocks of nutrition, the baby may have problems with a lack of energy, or have a buildup of chemicals that cannot be broken down and digested properly, which is dangerous due to its toxicity. “Timely detection of these problems allows treatment to prevent death, disease or disability,” says Dr Epton.
Does Baby Really Need These Tests?
If you’re wondering if you really need all these tests, Dr Tan strongly believes that you do. “In a nutshell, all the screening tests play a pivotal role in detecting medical conditions which may potentially be treatable and reversible. The importance of these tests should not be taken lightly. They may be even life-saving and there is absolutely no reason for any parent to reject them as it is clear that these tests confer benefits to the general well-being of a newborn,” he says.
However, he adds that it is important to know that these tests “are for screening purposes and therefore, they are not 100 per cent accurate. Some cases may still be missed, and that further tests are required to confirm the findings once the screen turns out positive.”