The anatomy scan, often called the Level 2 ultrasound or 20-week scan, is a detailed examination typically performed during the second trimester of pregnancy. This procedure uses sound waves to create images, allowing healthcare providers to assess the developing fetus, the placenta, and surrounding structures. The scan checks the baby’s growth and internal anatomy, providing information about the heart, brain, spine, and other organs for prenatal care.
The Purpose of Bladder Preparation
A full bladder is requested for the initial portion of the transabdominal ultrasound to improve image clarity. The fluid acts as an acoustic window, efficiently transmitting sound waves from the transducer. This fluid-filled structure pushes gas-filled bowel loops out of the pelvic area, preventing them from scattering sound waves and obscuring the view.
By distending the bladder, the uterus is slightly elevated and positioned more optimally for viewing. This elevation helps in thoroughly assessing the lower uterine segment, the cervix, and the placenta’s location. Proper visualization of these maternal structures is a necessary part of the anatomy scan protocol, maximizing the technician’s ability to capture required measurements accurately.
Practical Hydration Instructions
The quantity of water needed varies between clinics, but a typical recommendation for the anatomy scan is to consume approximately 16 to 24 ounces of fluid. This volume is roughly equivalent to two to three standard glasses of water. Drinking should be finished about 60 to 90 minutes before the scheduled appointment time to allow the fluid to reach the bladder and create the acoustic window.
It is advised to choose plain water for preparation, as non-carbonated beverages are easier on the stomach and less likely to cause gas, which interferes with sound waves. Avoid fluids containing caffeine, such as coffee or certain teas, because they act as diuretics and can cause the bladder to empty too quickly. The goal is to achieve a noticeably full bladder without causing pain or significant distress. Always follow specific instructions provided by the clinic.
What to Expect During the Scan
The anatomy scan typically lasts between 30 and 60 minutes, depending on the baby’s position. The procedure begins with the patient lying on an examination table while a trained sonographer applies warm gel to the abdomen. A handheld transducer is then pressed gently against the skin and moved across the belly to capture images.
The sonographer systematically examines various structures, including the four chambers of the heart, the brain’s hemispheres, the spine, and all four limbs. Internal organs, such as the kidneys, stomach, and bladder, are checked to confirm normal development. The location of the placenta, the volume of amniotic fluid, and measurements of the baby’s size are also recorded to assess overall growth. The full bladder is often only needed for the initial imaging of the cervix and lower structures, and the patient may be allowed to empty their bladder later if discomfort becomes too great.
Troubleshooting Common Issues
Issues with bladder fullness or the baby’s position can occur despite careful preparation. If the discomfort from holding urine becomes severe or painful, communicate this immediately to the sonographer. In cases of over-fullness, the technician may permit partial voiding to relieve pressure while maintaining enough fluid for the required images.
If the bladder is insufficiently full, resulting in poor image clarity, the sonographer may ask the patient to drink additional water and wait 15 to 20 minutes. If the baby is positioned poorly, such as curled up or facing away, common tactics are employed to encourage movement. The technician might suggest a short walk, a change of position, or consuming a small sugary snack or cold drink to stimulate the baby into a better viewing angle.