Termination for Medical Reasons, or TFMR, is when a pregnancy is terminated due to a chromosomal, genetic or structural fetal abnormality, or where continuing the pregnancy would risk the health or life of the mother.
Whilst most pregnancies result in the birth of a beautiful healthy baby. In some cases, soon to be parents are told the heartbreaking news that their unborn child is ill or has a condition. The conditions can range on a scale of severity from minor to life threatening.
Parents are then faced with the agonising decision as to whether to continue with the pregnancy or terminate it due to this medical reason. Sadly, it is something that happens every day around the world, although it is rarely spoken about.
Identification of an Issue
As medicine and science continues to evolve it provides prospective parents with information about their baby earlier than ever before. This information can provide joy and reassurance but, in some cases, it can highlight issues with the pregnancy or the baby.
NIPT (non-invasive prenatal test)
At around 10 weeks into a pregnancy a couple can pay to have a test called a non-invasive prenatal test (NIPT) which is a genetic blood test. During pregnancy a mother’s blood contains small fragments of a baby’s DNA. Because of this a simple blood test, taken from the mother, can identify the risk of certain genetic conditions at the chromosome level. This means that as well as identifying the baby’s gender, it can also identify if there are too few or too many chromosomes. It is important to note that this test DOES NOT identify all genetic conditions. Only certain abnormalities at a chromosome level. This test will tell couples if their baby is high or low risk of having one of these chromosome issues.
Nuchal Translucency (NT) Test
A second test that can be done instead of, or in conjunction with the NIPT, is a nuchal translucency (NT) ultrasound. This is an ultrasound that is normally conducted between 11 and 14 weeks. This investigation measures the thickness of the Nuchal Fold, a region behind the neck of the fetus. The result is entered into an algorithm along with the results of a blood test that assesses three specific proteins in the mother’s blood. The outcome of this test indicates whether the baby is high or low risk of having a chromosome abnormality. For example, trisomy 13, 18 and 21. A larger measurement indicates the baby may have an increased risk of something being wrong that is not necessarily genetic, for example, a cardiac abnormality.
Accuracy of Testing
Of the two investigations, the NIPT is more accurate, being a direct test of the fetal DNA in maternal blood. It does however incur some costs. The NT is an older test, less expensive and indirect, in so much as it gains information by comparing the mother’s result to other women and returning with a relevant risk of a given condition.
Using these methods, a large proportion of medical issues are identified in the first trimester or early second trimester. However, some fetal structural abnormalities remain undiagnosed until 19 to 20-weeks, when fetal anatomy is clearer on an ultrasound.
It is important to note that NIPT test, the NT test and ultrasounds are only screening tests and are not diagnostic. This means they can only tell you if there are indicators showing the baby is high risk. The NIPT and NT tests can provide false positives. This is where they say the baby is high risk, however the diagnostic test shows the baby is healthy. These investigations, particularly the NIPT are said to be 99% accurate in diagnosing chromosomal conditions.