Anomaly Scan – Everything you need to know

Pregnancy is a journey that is characterised by milestones that are also accompanied by excitement and a strong sense of responsibility. Among these, the anomaly scan stands out as a critical diagnostic event. The 20-week ultrasound, as it is also known, has offered an insight into the womb, and as a result, healthcare practitioners have a chance to analyse the structural development of the fetus with incredible accuracy.

It is necessary to learn the peculiarities of this process, in what cases it is observed, when it happens and how to be prepared in case of a newborn child. Every expecting mother should know it. This guide provides a comprehensive overview of the level 2 ultrasound, ensuring you are well-informed and empowered throughout your second trimester.

What is an Anomaly Scan and Why is it Performed?

An anomaly scan is a specialised ultrasound examination typically conducted between the 18th and 21st weeks of pregnancy. While earlier scans primarily focus on confirming the pregnancy and dating the gestation, the level 2 ultrasound is a thorough "head-to-toe" assessment of the baby's physical development.

The main goal is to examine the feasibility of the structural abnormalities in the organs and limbs of the foetus (alloys). The sonographer carefully studies the brain, face, spine, heart, stomach, kidneys and limbs. In addition to the anatomy of the baby, it is also possible to assess the location of the placenta, the volume of amniotic fluid and the flow of blood in the umbilical cord through the scan. This thorough examination is conducted to ensure that the pregnancy is healthy and to detect any problems that may need medical care before or after delivery.

The Role of Early Detection

Early detection through an anomaly scan is pivotal. The early detection of a condition enables parents and caregivers to communicate on possible treatment options, arrange in advance specialised care at birth or even undergo surgeries that may be required right after the delivery of the baby. In other instances, some of the conditions can be cured even before the baby is born. 

What Does the Sonographer Look For During a Scan?

In the process, the sonographer inserts a high-frequency sound wave into the abdomen with a transducer that makes a detailed 2D (and occasionally 3D or 4D) image. They have a rigid checklist so that no section of the anatomy is missed.

The Head and Brain

The sonographer examines the form and bulk of the skull. They seek such conditions as anencephaly (the incomplete formation of the brain and skull) and check the inner structures of the brain to make sure that they are developing symmetrically.

The Face and Spine

One of them is the examination of a cleft lip. A cleft palate is more difficult to observe, but the lip is easily visualised. Spinal formation is also examined in longitudinal and cross-sectional examination to find out whether the vertebrae are aligned properly and the skin fully covers the spinal cord, i.e. conditions such as spina bifida.

The Heart and Lungs

Hearts are studied based on the four chambers and the great vessels going to them and out of them. The sonographer searches for severe cardiac defects. They also examine the diaphragm to confirm that the chest and abdominal organs are separated well, and they are investigating the presence of a diaphragmatic hernia.

The Abdomen and Limbs

The stomach, kidney and bladder are determined to be present and functional. The sonographer examines the abdominal wall as well to make sure that it is complete and rules out gastroschisis or exomphalos. Lastly, hands, legs, feet, and arms are examined with regard to proper development and alignment of the bones.

How to Prepare for Your Anomaly Scan Appointment?

Preparation for an anomaly scan is relatively straightforward, but a few small steps can make the experience smoother and help the sonographer get the best possible images.

Physical Preparation

Contrary to other early scans, a full bladder is not always necessary to conduct a 20-week scan because the baby will be big enough and visible. Nevertheless, it is recommended that a moderately full bladder be used by many clinics to assist in raising the uterus further into the abdomen. Wearing two-piece clothing, which is comfortable, is also desired, as you will have to expose your belly between the ribs and pubic bone.

Promoting the Movement of the Baby

The success of a level 2 ultrasound is often a collaborative effort between the sonographer's skill and the baby's cooperation. In case the baby is camera shy or lying in such a manner that essential organs are not in sight, the sonographer will employ a couple of techniques to make the baby change the position. Asking the mother to walk briefly around the clinic, taking small and quick strides, is one of the most frequent techniques. The rhythmic motion and the shift in the gravity usually provoke the foetus to move. Likewise, the sonographer may recommend the intake of a cold or sweet drink, e.g. fruit juice or ice water. Sudden temperature shift or even the slight rise in the blood sugar of the mother can awaken the baby, and then the baby will kick and stretch a lot, giving the technician the angles that he/she requires.

These medical needs are less difficult to handle with the proper support system in place. The option of Niva Bupa Health Insurance as a provider means one will be covered by a huge network of more than 10,000 hospitals. Their "M-iracle" feature in certain plans even covers advanced maternity needs like IVF and complications, providing a safety net that extends far beyond the routine anomaly scan.

Comparing the Anomaly Scan with Other Prenatal Tests

The real purpose behind each scan would need further examination of the medical objectives of every trimester. NT Scan (Nuchal Translucency) is a screening method that is conducted within the 11-14 weeks and is used mainly in the diagnosis of chromosomal diseases such as Down syndrome. It is an indicator of the amount of clear space at the back of the neck of the baby; an excessive thickening at the back might signify an increased probability of the development of some genetic problems. This is commonly accompanied by a blood test to give a combined risk assessment in the form of a heads-up call to parents and doctors.

The anomaly scan, which takes place during the second trimester, shifts the focus from chromosomal screening to a detailed structural evaluation. At this age, the baby has grown big enough so that the sonographer ensures that the heart, brain and limbs are physically developed in proper fashion. While the NT scan looks for markers of risk, the level 2 ultrasound looks for physical evidence of development. It is the best examination that a physician gets to view the anatomy of the baby prior to it being born, so that the internal organs are in their right place and working properly.

Growth Scans (also known as well-being scans) are also commonly performed during the last trimester of the pregnancy, starting at 28 weeks. Unlike the fetal development scan, which is a one-time detailed inspection, growth scans may be performed multiple times to track the baby's trajectory. Such scans are used to determine the head circumference, abdominal girth and the length of the femur to predict the weight of the baby. They also examine the functionality of the placenta and the amount of the amniotic fluid, and make sure that the environment is favourable to the baby as it gets ready to be born.

Conclusion

The anomaly scan is a cornerstone of modern prenatal care. It offers unmatched peace of mind to parents and the essential information to healthcare workers, which will guarantee that all the preparations involved in the arrival of the baby are done with accuracy. Although the thought that the scan will come and the scan process itself may be terrifying, it is an important procedure in terms of preserving the health of both the mother and the child.

With the health insurance plan at Niva Bupa, the financial safety, coupled with frequent medical examinations, you are bound to sail through the pregnancy process with peace of mind. Being ready is the best present you can give your family in growing months, whether it is the routine visits that the second trimester brings or the surprise needs of the third trimester.

FAQs

1. What is the anomaly scan done for?

The anomaly scan, commonly called the 20-week ultrasound, is a detailed screening test performed to assess the physical development and structural health of the foetus. It is primarily aimed at identifying congenital or structural abnormalities that can influence the organs of the baby, the spine, brain, face, or heart. Various complications like spinal bifida, cleft lip and major heart defects might be detected at this level.

Besides identification of the abnormalities, the scan aids in tracking the baby's growth. The abdomen, head, and thigh bone (femur) measurements are also made to determine that the foetus is developing according to the gestational age. The scan also determines the position of the placenta, the size of the amniotic fluid and the blood flow in the uterus. If any concerns are found, the fetal development scan allows doctors and parents to plan appropriate medical care, which may include specialised monitoring, treatment, or delivery planning.

2. How is gender identified in an anomaly scan?

During the second-trimeste rFetal development scan, foetal gender may be identified by visualising specific anatomical features. The presence of the penis, scrotum, and testicles is taken as an indicator in a male foetus. The vulva, labia and clitoris can be observed in a female foetus.

In other instances, they also use the angle of the genital tubercle, or other internal pelvic organs like the uterus and ovaries, to reinforce the results of the findings (Schwartz 2008). But correctness is conditioned by the position of the foetus, the quality of the image and the gestation age. It should be mentioned that in such countries as India, sex determination during the prenatal period is legally forbidden.

3. Which is better: NT scan or anomaly scan?

Neither the NT scan nor the anomaly scan is better than the other; they serve different purposes and are performed at different stages of pregnancy. An NT (Nuchal Translucency) scan is carried out at the age of 11-14 weeks and is primarily conducted to determine the likelihood of chromosomal abnormalities like Down syndrome.

The detailed fetal scan, performed between 18 and 22 weeks, is a detailed structural examination of the foetus. It is concerned with the assessment of the organs of the baby, its limbs, spine, and physical development. Therefore, physicians typically order both scans as they offer a more detailed picture of foetal health, as one can determine the genetic risk and the other can analyse physical anatomy.

4. Why do the physicians take 20 weeks to do a gender ultrasound?

Doctors prefer to wait until the 20-week anomaly scan to assess foetal gender because accuracy is much higher at this stage. At 18 to 22 weeks, the sex organs of the baby are also completely developed and can be easily identified, making it more accurate, and in most cases, its accuracy is more than 95%.

In the earlier pregnancy period, say at 12 or 14 weeks, the genital structures are very close, which makes the probability of error too high. Since the mid-pregnancy ultrasound is already a routine, comprehensive examination of the foetus, it becomes the most practical and efficient time to evaluate gender, where legally permitted.