My doctors are doing a 4d ultrasound at 26 weeks and giving me a stuffed animal with my baby's heartbeat (soundbox) and I have medi-cal (free insurance or state insurance idk what it'd be considered lol)

dumb lol

Because they aren't medically necessary.

I think because they aren't meant to diagnose or see the growth progress of the baby. Also i think that u/s are covered up to a certain point in pregnancy. The 3d/4d might be considered cosmetic in the insurance eyes.