Non-Invasive Pre-Natal Testing (NIPT)
What is pre-natal testing?
Many women who achieve a pregnancy, naturally or with fertility treatment, are anxious to know as soon as possible that their baby is healthy. As a woman gets older, the risk that her baby may be affected by genetic problems, such as Down’s Syndrome, gets higher.
Current screening tests such as the ‘triple test’ or nuchal translucency scanning are non-invasive (and so do not put the pregnancy at risk) but are not definitively conclusive. Other tests such as CVS (Chorionic Villus Sampling) or amniocentesis carry a small risk of inducing a miscarriage in a normal pregnancy.
Non-invasive pre-natal testing (NIPT) analyses cell-free DNA (cfDNA) circulating in the pregnant mother’s blood. It is a new option in pre-natal screening:
- for Down’s syndrome (trisomy 21)
- other common chromosomal conditions (trisomies 18 and 13)
- X and Y chromosome conditions
- it can also reveal the gender (sex) of the baby
Who may benefit from NIPT?
This test can be requested for any singleton or twin pregnancy, including those conceived naturally or by IVF using the patient’s own egg or a donor egg.
However, the sex chromosome (X and Y) analysis is not available for twin pregnancies.
At IVI Midland, a member of the clinical team will discuss the reasons for undertaking the test – and the possible outcomes. The results are also given by a member of the clinical team, who can offer support as needed.
What does the test involve?
The NIPT can be done from 10 weeks of pregnancy.
DNA from the fetus circulates in the mother’s blood. Cell-free (cfDNA) occurs after the natural breakdown of fetal cells from the placenta and disappears from the mother’s blood stream soon after giving birth.
During pregnancy, cfDNA can be tested to give the most accurate estimate of the risk of a fetus having a common chromosome condition – called a trisomy. This occurs when there are three copies of a particular chromosome instead of the normal two.
The test detects the following trisomies:
- trisomy 21 is the most common trisomy at the time of birth. Also called Down’s syndrome, it is associated with moderate to severe intellectual disabilities and may also lead to digestive disease, congenital heart defects and other malformations
- trisomy 18 (Edward’s syndrome) and trisomy 13 (Patau syndrome) are associated with a high rate of miscarriage. Babies with these are born with severe brain abnormalities and often have congenital heart defects, as well as other birth defects. Most babies affected by these die before or soon after birth, and very few survive beyond the first year of life
- sex chromosome conditions. The sex chromosomes (X and Y) determine whether we are male or female. X and Y chromosome conditions occur when there is a missing, extra, or incomplete copy of one of the sex chromosomes. The test can assess risk for:
- XXY (Klinefelter’s syndrome)
- a missing X chromosome in a girl (Turner’s syndrome)
There is significant variability in the severity of these conditions, but most individuals have mild, if any, physical or behavioural features.
If the mother is interested in having the optional sex testing, she should talk to a member of the IVI Midland clinical team to determine if it is right for her. This option is not available for twin pregnancies.
Are there any risks?
NIPT is non-invasive: it involves taking a blood sample from the mother. The pregnancy is not put at risk of miscarriage, or from other adverse outcomes that are associated with invasive testing procedures, such as amniocentesis.
How accurate is the test?
Clinical studies have shown that the NIPT has exceptional accuracy for assessing fetal trisomy risk.
A ‘high risk’ result is indicative of a high risk for a trisomy. The test identifies in singleton pregnancies:
- more than 99% of fetuses with trisomy 21 (Down’s syndrome)
- 98% of fetuses with trisomy 18 (Edward’s syndrome)
- 80% of fetuses with trisomy 13 (Patau syndrome)
- 96% of fetuses with Turner’s Syndrome
- more than 99% accuracy for fetal sex via the X and Y analysis
Accuracy for detecting other sex chromosome anomalies varies by condition.
How to make an appointment
Simply call the number below to make an appointment. Remember, the NIPT is available for natural conception clients, IVI Midland patients, and women who have conceived at other fertility clinics, from as early as 10 weeks.
Cost of NIPT at IVI Midland: £450.00
Go to Fees section