By Sola Ogundipe
SICKLE Cell Disease, SCD is a group of inherited red blood cell disorders in the world.
The Non-invasive Prenatal Test, NIPT is important as it does not only screen for chromosomal abnormalities like Down Syndrome, Edward Syndrome, Patau Syndrome as well as gender identification early in pregnancy, its does much more than that.
Normal red blood cells are round and move around to carry oxygen to all parts of the body. But in someone with SCD, the red blood cells are “sickle-shaped” and they die early, causing a constant shortage of red blood cells.
As these abnormal red blood cells travel through small blood vessels, they get stuck and clog the blood flow. This can cause pain and other serious problems such as infection, acute chest syndrome, and stroke.
From clinical records, Nigeria has the highest birth prevalence of SCD in the world. An estimated 1 in 4 Nigerians have the sickle cell trait (AS genotype), meaning they are carriers of one sickle cell gene, but they do not suffer from the disease.
It is known that if both parents are carriers of the sickle cell gene (SS), there is a 25 percent chance that their baby could be born with the condition. The frequency of SCD in Nigeria is about 20 per 1000 births resulting in about 150,000 babies being born annually with sickle cell anaemia, which is the most common form of sickle cell disease.
Previously, the risk status of an unborn baby used to be determinable through invasive methods or delayed until newborn screening results are available. The good news is that Nigerian couples who might be at increased risk of having a baby with SCD can now screen their unborn babies for the genetically inherited blood condition without any risk to the fetus.
The test which is carried out in the first trimester is known as the Non-invasive Prenatal Test, NIPT. This test is currently being provided by Teocare Genomics in Lagos.
The NIPT is a highly accurate non-invasive prenatal test that screens for SCD from as early as the 11th week of pregnancy.
With the availability of the NIPT test, all that is required is a screening of the pregnant woman’s blood for prenatal detection of the disease.
The NIPT screening enables intending parents and healthcare providers to make informed decisions about diagnostic testing, and it also expands gene therapy treatment options. According to Teocare Genomics, the NIPT test provides a significantly stronger risk indication than traditional screening procedures such as amniocentesis, which is an invasive test.
With a high sensitivity rate, NIPT is ensuring that the number of women undergoing invasive diagnostic procedures is significantly reduced in Nigeria.
For SCD, the NIPT test enables intending parents to make informed choices based on information about the baby’s risk of inheriting the disease. The test is non-invasive because the sample is drawn from the woman’s blood, unlike former invasive methods that took samples from the baby leading to unwanted outcomes such as infection and miscarriage.
With NIPT, there is zero risk to the mother and the fetus because it is noninvasive. The test works because there is free fetal DNA in the pregnant mother’s blood that can be detected from 11 weeks upwards.
While the NIPT test is not a diagnostic test, it tells you that the fetus has increased risk so you now have to do a diagnostic test to determine if it is positive. This technology is available in Nigeria and is done by Teocare Genomics in Lagos.
On request, the NIPT test also detects the sex chromosomes at 10 weeks amid other chromosomal abnormalities. Ordinarily, every pregnant woman should be doing the NIPT test and it is best done early so that decisions can be taken early.
Before the test, there is pre-screening counseling, where you as the intended parents are counseled and told all that you need to know about the implications of the result and your options, so that you can make up your mind.
Information that is obtained about any potential risk to the fetus is crucial, but the final decision about what to do is up to you. It is your choice, what is important is making an informed choice