Pregnancy Ultrasound (complete, after first trimester)

What it is

By the second trimester the fetus is large enough for its anatomy to be examined piece by piece, and this scan does exactly that. The sonographer works through a defined checklist: the brain and skull, the face and lips, the spine, the four chambers of the heart and the vessels leaving it, the stomach, kidneys and bladder, the abdominal wall, the arms and legs, the hands and feet. Alongside the anatomy come measurements — head, abdomen, thigh bone — which together estimate size and how growth is tracking. The placenta is located and its relationship to the cervix noted, and the volume of amniotic fluid is assessed. The word "complete" in this code is the distinction that matters: it separates this full survey from the short, targeted scans done later in pregnancy to check one thing, which are billed under different codes.

Why it is done

• To examine fetal anatomy in detail and look for structural differences
• To measure the fetus and estimate growth and weight
• To locate the placenta and check whether it lies over or near the cervix
• To assess the amount of amniotic fluid
• To confirm the number of fetuses and, in a multiple pregnancy, how they are arranged
• To identify the position the fetus is lying in

What to expect

This is done through the abdomen. Gel is applied and the probe is moved across the belly, sometimes with firm pressure to get past a limb or to coax a change in position. It is longer than most people expect — often thirty to forty-five minutes, and longer again with twins, or when the fetus is lying in a way that hides a structure the sonographer has to document. It is common to be asked to walk around, roll onto a side, or come back another day to complete views that could not be obtained; that is a positioning problem, not a finding. The sonographer takes the images and a physician interprets them, so a full answer generally comes from the obstetrician rather than in the room.

Questions worth asking

• If some views cannot be obtained and you are asked to return, ask whether the repeat visit is billed as a follow-up scan or as a full study again.
• Ask whether your obstetric practice bills a global maternity package and whether this scan sits inside or outside it.
• If you are referred to a maternal-fetal medicine specialist for a more detailed scan, that is a different and higher-priced code — ask what it is before going.
• In a twin pregnancy, ask whether the charge is per fetus.
• Keepsake or elective imaging offered alongside the medical scan is generally not covered. Ask for that to be quoted separately and in advance.