The anatomy scan, often called the Level 2 ultrasound or anomaly scan, is a standard, detailed check of a developing fetus performed during the second trimester of pregnancy. This non-invasive procedure uses sound waves to create images of the baby’s internal structures and to assess growth and development. The main purpose of this examination is to confirm the fetus is developing appropriately and to screen for structural abnormalities. The actual time spent scanning typically ranges from 30 to 60 minutes, providing a comprehensive look at the baby’s full anatomy.
The Standard Duration of the Anatomy Scan
The typical scheduled time for an anatomy scan is approximately 45 minutes, though appointments frequently extend up to a full hour. This duration accounts for the sonographer’s need to systematically capture dozens of precise measurements and views. The technician must follow a strict protocol, which requires careful manipulation of the ultrasound wand and adjustment of equipment settings to obtain clear images. This time includes the active scanning period and documentation of biometric data, such as head circumference and femur length, used to estimate fetal weight and age.
The scan is a targeted, high-resolution examination, not a brief check. The sonographer must not only locate structures but also measure them against established gestational norms. If the baby is in an optimal position from the start, the process can be completed closer to the 45-minute mark. The thoroughness of this systematic organ check is the primary reason why this appointment is significantly longer than earlier, more basic ultrasounds.
Detailed Components of the Examination
The scan provides a comprehensive anatomical survey. The sonographer dedicates significant time to the fetal brain, examining structures like the lateral ventricles, the cerebellum, and the cavum septum pellucidum. Correct visualization of these areas helps confirm proper neurological development. An examination of the four chambers of the heart, along with the major outflow tracts, is also a lengthy part of the process.
The technician will systematically check the spine in both transverse and longitudinal planes to confirm the integrity of the vertebrae and skin line. The abdominal organs are assessed to ensure the stomach bubble, kidneys, and bladder are present and functioning correctly. Measurements of the long bones, such as the femur and humerus, are taken to monitor growth symmetry and proportionality. The scan also confirms the location of the placenta and measures the volume of amniotic fluid, which is important for fetal lung development and movement.
Factors That Can Lengthen the Appointment
Several variables can cause the anatomy scan to exceed the typical 60-minute window. The most frequent delay is the fetus being in a non-cooperative position. If the baby is lying in an awkward way, the sonographer cannot obtain the required views of the heart or face. In these cases, the parent may be asked to walk around or drink a cold, sweet beverage to encourage the baby to move into a better orientation.
Maternal body habitus can also affect the clarity of the ultrasound images. If the sonographer detects an area that is difficult to visualize or finds a measurement that falls outside the expected range, they may spend additional time trying to clarify the finding. If a potential anomaly is suspected, the sonographer may need to pause and consult with a supervising radiologist or physician, which can add significant time to the appointment.
Preparing for the Scan and Next Steps
Preparing for the anatomy scan involves a few simple steps that can help the appointment run smoothly. While some facilities no longer require a completely full bladder, adequate hydration can help elevate the uterus, which sometimes improves the clarity of the images. Wearing loose-fitting clothing makes it easier for the sonographer to access the abdomen for the transabdominal scan. Some providers recommend eating a small snack beforehand to encourage fetal movement, which aids in obtaining hard-to-get views.
Following the completion of the scan, the sonographer may offer preliminary findings, such as the sex of the baby if requested. However, they cannot provide a full, definitive report, as the images and measurements must be formally reviewed by a physician. The official report is then sent to your primary obstetrician or midwife, who will discuss the results with you at a follow-up appointment. If the scan was incomplete due to the fetal position, a follow-up visit may be scheduled to capture the remaining required images.