Should I have an NT scan?
I am 8 weeks pregnant and this is my first pregnancy. I’m not sure if I need to get an NT ultrasound done. I have been told different things: one GP has told me that I should get it done, and another has told me that I do not need to get it done because it is only recommended for women over 35 years old and I’m 31 years old. I’m really confused and feel like I’m not really getting any valuable advice and I’m really nervous considering this is my first pregnancy. It would be great to hear your opinion.
Our midwife Melissa says:
The NT ultrasound is an ultrasound screening tool that is used to assess the level of risk of your baby having three chromosomal abnormalities, including Down syndrome. Â It is commonly referred to as the 12-week scan, with many women believing it to be a routine ultrasound.
Women are not considered to be at high risk of carrying babies with chromosomal abnormalities unless they are aged 35 and over; consequently, many women are not offered the NT scan unless they are over 35 years of age. Â Other practitioners routinely offer the scan to all women. Â Either way, it remains a personal decision whether to have the scan or not.
Many women view the NT scan as an opportunity to see the baby and to bond with the baby, and this certainly will happen, however, it is worth noting that the NT scan it is a medical test that will answer a medical question. That question is to quantify the chance of a baby having a chromosomal abnormality. Â If the risk comes back as being greater than 1:300, then we would consider the baby to be at high risk, whereas if the risk comes back at less than 1:300 (such as 1:1000), then we would say that the baby is at low risk. However, even with a very high risk result, there is still a very good chance that the baby is fine, and conversely, even with a very low risk result (eg 1:15,000), the baby may unfortunately be that one that is affected.
If the NT scan yields a high risk result, the next decision is whether to find out for sure if there is a chromosomal abnormality, and this would involve an amniocentesis. Amniocentesis involves inserting a needle into the uterus via the woman’s abdomen and withdrawing some fluid from around the baby that contains some of the baby’s cells. These cells are then cultured and the chromosomes are analysed for abnormalities.  If the amniocentesis does show that there is a problem with the baby’s chromosomes, the next decision point is whether to continue the pregnancy.  This is of course a very difficult decision.
Essentially, as a 31 year old woman, you are in a low risk group for chromosomal abnormalities of your baby. Â It would not be recommended that you have the NT scan, however individual choice plays an important part in your final decision. Â If you are concerned and would like to be screened, your midwife or doctor can refer you for the scan.
This answer was written for Birth by midwife Melissa Maimann from Essential Birth Consulting.
