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In the near future, Pre-natal testing may become a simple blood test without risk to you or your baby.  A technician need only draw a small blood sample from your arm to detect health of fetus.

New Noninvasive and effective Prenatal Testing

Non Invasive Prenatal Diagnosis (NIPD) is a new genetic test to screen for birth defects and inherited disease. Now available only to women with high-risk pregnancies, many experts feel it should become a standard test. It is projected to become standard for use by the National Health Service in the United Kingdom sometime this year.

A National Institute for Health Research (NIHR) study carried out to provide Noninvasive prenatal testing (NIPT) has reported its successful results to the annual conference of European Society of Human Genetics.

Presenting her team's findings, Professor Lyn Chitty, from the Institute of Child Health and Great Ormond Street Hospital, London, UK, will announce the possibility for introducing NIPT into the British National Health Service (NHS) as a screen for Trisomy 21 (Down's syndrome).

As part of the study carried out by the NHS laboratory at Great Ormond Street Hospital, women at high and medium risk of having a child with Down's syndrome were offered NIPT, and over 2,500 undertook the test.

Prof Chitty: "There was a very high uptake in testing and we saw invasive test numbers fall sharply. NIPT performed well in identifying problems — and women were very positive. The cost of providing an NIPT service will depend on the cost of the test itself and how it is implemented. Significant savings will result from a decrease in invasive testing while increasing the detection of affected babies. The reduction in invasive testing also means there will be a reduction in miscarriages and loss of unaffected babies — which is much better for parents."

Commenting on NIPT, a woman classified as 'high risk' and part of the study added: "You get told 1 in 30 and although that sounds relatively high...we probably wouldn't have done [invasive testing] because there's a risk of miscarriage... I think that we were very lucky. It's enabled us to make an informed choice about what happens for the rest of our lives."

Reporting the results of a second study from the same group, Dr Suzanne Drury, a translational research and development scientist from Great Ormond Street Hospital, described her team's experience in the use of NIPD to diagnose the disorder congenital adrenal hyperplasia (CAH). CAH exposes a female fetus to male hormones, which can result in the development of masculinised external genitalia. It's an autosomal recessive (AR) disorder, in which the defective gene must be passed on from both parents.

Dr Drury: "We chose CAH because the gene that causes it is particularly challenging to study. It is the most common adrenal disorder in childhood and affects one in every 18,000 live births. In the UK, NIPD for fetal sex determination is carried out for an average of 13 pregnancies per year at risk of CAH because it is the female fetus at risk.

"Fetal sex determination allows testing to see if the female fetus is carrying two mutant copies of the CAH gene and is therefore affected. As there is an available in-utero treatment for CAH, we felt this was a good condition to select allowing treatment for specifically targeted, affected female fetuses."

In 2014, 32% of prenatal diagnostic tests for monogenic disorders in Dr. Suzanne Drury's laboratory were with NIPD. NIPD for single gene disorders in a fetus is diagnostic, it targets only specific genetic changes present in a high risk family. For this reason it will remove the need for invasive testing completely, reducing the risk of miscarriage and making prenatal diagnosis for these conditions safer and more accessible to families who would not otherwise take the risk.

Dr Drury adds: "Our results have shown NIPD to be sufficiently precise to be diagnostic and therefore we do not recommend confirmatory invasive testing. Currently we are developing non-invasive tests for other conditions caused by mutations in a single gene, including cystic fibrosis, sickle cell anaemia, and beta-thalassaemia. At present invasive testing is required for definitive prenatal diagnosis of these disorders, but our experience with CAH leads us to believe that NIPD will have the same diagnostic efficacy in other AR disorders."

The researchers presented their study to the UK National Screening Committee and hope that it will inform their decisions on if and how to implement NIPT into the National Health Service (NHS) within the UK.

Presenter remarks:
Reporting the results of a second study from the same group, Dr Suzanne Drury, a translational research and development scientist from Great Ormond Street Hospital, will describe the team’s experience in the use of NIPD (non-invasive prenatal diagnosis) to diagnose the disorder congenital adrenal hyperplasia (CAH). CAH exposes a female fetus to male hormones, which can result in the development of masculinised external genitalia. It is an autosomal recessive (AR) disorder, in which the defective gene must be passed on from both parents in order to cause disease.

Dr Drury will say: “We chose CAH because the gene that causes it is particularly challenging to study. It is the most common adrenal disorder in childhood and affects one in every 18,000 live births. In the UK, NIPD for fetal sex determination is carried out for an average of 13 pregnancies per year at risk of CAH because it is the female fetuses that are at risk.

“Fetal sex determination allows targeting of invasive testing to see if the female fetus is carrying two mutant copies of the CAH gene and is therefore affected. As we were already carrying out NIPD for sex determination, and there is a potential in utero treatment for CAH available, we felt that this was a good condition to select to allow treatment to be very specifically targeted to only those female fetuses that are affected.”

In 2014, the researchers say, 32% of prenatal diagnostic tests for monogenic disorders in their laboratory were non-invasive. NIPD for single gene disorders in a fetus is diagnostic, as it targets specific genetic changes present in a high risk family. For this reason it will remove the need for invasive testing completely, reducing the risk of miscarriage and making prenatal diagnosis for these conditions safer and more accessible to families who would not otherwise be prepared to take the risk.

Dr Drury adds: “Our results have shown NIPD to be sufficiently precise to be diagnostic and therefore we do not recommend confirmatory invasive testing. Currently we are developing non-invasive tests for other conditions caused by mutations in a single gene, including cystic fibrosis, sickle cell anaemia, and beta-thalassaemia. At present invasive testing is required for definitive prenatal diagnosis of these disorders, but our experience with CAH leads us to believe that NIPD will have the same diagnostic efficacy in other AR disorders.”

Date: 16 Jul 2014  -  Regarding NIPD use within the United States:

Evaluation of non-invasive prenatal testing (NIPT) for aneuploidy in an NHS setting: a reliable accurate prenatal non-invasive diagnosis (RAPID) protocol

Abstract
Background
Non-invasive prenatal testing (NIPT) for aneuploidies is now available through commercial companies in many countries, including through private practice in the United Kingdom (UK). Thorough evaluation of service delivery requirements are needed to facilitate NIPT being offered more widely within state funded healthcare systems such as the UK’s National Health Service (NHS). Successful implementation will require the development of laboratory standards, consideration of stakeholder views, an analysis of costs and development of patient and health professional educational materials.

Methods/Design
NIPT will be offered in an NHS setting as a contingent screening test. Pregnant woman will be recruited through six maternity units in England and Scotland. Women eligible for Down’s syndrome screening (DSS) will be informed about the study at the time of booking. Women that choose routine DSS will be offered NIPT if they have a screening risk ≥1:1000. NIPT results for trisomy 21, 18, 13 will be reported within 7–10 working days. Data on DSS, NIPT and invasive testing uptake, pregnancy outcomes and test efficacy will be collected. Additional data will be gathered though questionnaires to a) determine acceptability to patients and health professionals, b) evaluate patient and health professional education, c) assess informed choice in women accepting or declining testing and d) gauge family expenses. Qualitative interviews will also be conducted with a sub-set of participating women and health professionals.

Discussion
The results of this study will make a significant contribution to policy decisions around the implementation of NIPT for aneuploidies within the UK NHS. The laboratory standards for testing and reporting, education materials and counselling strategies developed as part of the study are likely to underpin the introduction of NIPT into NHS practice.

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