Get the scans you need on site. Our Registered Diagnostic Medical Sonographer, Sally Anderson, LPN, RDMS, provides obstetric and gynecologic ultrasound right here in our Tacoma office, including 8-week dating and 20-week anatomy scans.
What We Offer
Late Pregnancy Monitoring (36+ weeks)
Late Pregnancy Monitoring (36+ weeks)
What to expect when you get an ultrasound at Rainier OBGYN
Ultrasound (Sonography) Q & A
When are the first ultrasound scans?
How often should I have pregnancy ultrasounds?
For low‑risk pregnancies, many guidelines describe at least one or two standard ultrasounds: an early scan for dating and viability, and a “mid‑trimester” anatomy scan around 20–22 weeks to look carefully at the baby’s organs and the placenta. Additionally, Rainier OB/GYN prefers a scan to be done at 36 weeks to confirm that the baby is head down, the estimated fetal weight measured, and that there is adequate amniotic fluid around the baby. More frequent scans are done only when medically indicated, such as with twins, growth concerns, certain medical conditions, or follow‑up of a prior finding, and the exact schedule is set by your clinician.
Whats the difference between 3D and 4D scans?
A standard (2D) scan shows flat, cross‑section images that your clinician uses for medical measurements and diagnosis. A 3D scan uses computer processing to build a still, three‑dimensional image of the baby’s surface, while 4D adds real‑time movement (like a short video) to those 3D images, and these are usually considered optional, non‑essential add‑ons rather than core medical imaging.
How does an ultrasound scan determine the due date?
Early in pregnancy, the sonographer measures the embryo or fetus (most often the crown‑rump length in the first trimester) and the machine uses established growth charts to calculate a gestational age. That age is then converted to an estimated due date, which may replace or refine the due date based on your last menstrual period if the measurements differ beyond an accepted margin.
Can family attend?
Sonographers need a calm, quiet environment to focus and obtain detailed images with precision. Our policy allows each patient to be accompanied by one adult (18 years or older) for routine scans.
Will my insurance cover an ultrasound? / How many?
Health insurers cover medically indicated pregnancy ultrasounds ordered by a clinician, but coverage, copays, and limits differ by plan. Non‑medical, so-called 3D/4D scans, are not covered, so patients should contact their insurance company and Rainier OB/GYN’s billing office to confirm which exams are covered and how many are allowed under their specific benefits.
