An anomaly scan, also known as a mid-pregnancy ultrasound or 20-week scan, is an important prenatal test performed between 18 to 22 weeks of pregnancy. This detailed scan checks the developing baby for physical abnormalities or “anomalies” and assesses the baby’s growth and the condition of the placenta, amniotic fluid, and umbilical cord.
What is an Anomaly Pregnancy Scan?
The anomaly scan uses ultrasound technology to generate images of the baby inside the womb. It’s primarily designed to look for structural abnormalities or developmental issues in the baby’s organs and body parts. It’s a routine part of prenatal care and provides essential information for both the mother and healthcare providers.
What Does the Anomaly Scan Check For?
During the anomaly scan, the sonographer will check:
- Head and Brain: The scan evaluates the size and shape of the baby’s head and looks for signs of brain conditions like spina bifida or hydrocephalus.
- Face: The scan checks for cleft lip or other facial anomalies.
- Heart: The baby’s heart is examined in detail to detect congenital heart defects like holes in the heart or irregularities in the chambers.
- Spine: The scan ensures that the baby’s spine is forming normally and checks for conditions like spina bifida.
- Abdominal Organs: The sonographer checks the baby’s stomach, kidneys, and bladder to ensure they are in the correct position and functioning properly. Conditions like gastroschisis (organs developing outside the abdomen) can be detected.
- Limbs: The baby’s arms, legs, fingers, and toes are checked for any anomalies, such as clubfoot.
- Placenta: The position of the placenta is examined to rule out conditions like placenta previa (where the placenta is too low).
- Amniotic Fluid: The volume of amniotic fluid is measured to ensure it’s within the normal range.
- Umbilical Cord: The scan checks the umbilical cord for abnormalities, such as the number of vessels present (a normal cord has three vessels).
What Conditions Can the Anomaly Scan Detect?
While the anomaly scan does not detect every condition, it can identify or provide indications for:
- Congenital heart disease
- Cleft lip and palate
- Spina bifida
- Limb abnormalities
- Diaphragmatic hernia
- Kidney problems, such as hydronephrosis
- Brain abnormalities
- Skeletal dysplasia
- Gastroschisis and exomphalos (abdominal wall defects)
- Twins or multiple pregnancies, ensuring both babies are growing properly.
What Happens If an Abnormality is Found?
If the scan detects an abnormality, additional tests and scans may be recommended. These could include:
- Further ultrasounds to get more detailed images.
- Amniocentesis to test for chromosomal abnormalities like Down syndrome.
- Referral to a specialist for more detailed investigations and counseling on potential treatments or interventions.
In some cases, issues detected on the scan may resolve themselves, while in others, early detection allows for better planning and management during the pregnancy or after birth.
Is the Anomaly Scan Safe?
Yes, the anomaly scan is safe for both mother and baby. It’s a non-invasive procedure using sound waves to create images. No radiation is involved.
How Should I Prepare for an Anomaly Scan?
You usually don’t need any special preparation for the anomaly scan. You may be asked to drink water before the scan to fill your bladder, which helps get clearer images.
Conclusion
An anomaly scan is an essential part of prenatal care that helps detect potential issues with the baby’s development. Early detection allows for better management of pregnancy and planning for any necessary interventions post-birth. While it’s a routine scan, it plays a critical role in ensuring both the mother and baby’s health throughout pregnancy.