How many weeks pregnant is the most accurate time to do a four-dimensional B-ultrasound? With the change in fertility concepts and the maturity of technology, prenatal check-up for pregnant women has gradually become an indispensable part. Among them, four-dimensional B-ultrasound is a very important diagnostic method. So, how many weeks into pregnancy is the most accurate time to do a four-dimensional B-ultrasound? This article will elaborate on the gestational age, other examinations, matters needing attention, and the content of four-dimensional B-ultrasound to help pregnant women correctly grasp the time of prenatal examination and improve the accuracy of the examination. How many weeks into pregnancy is the most accurate? First of all, how many weeks into pregnancy is the most accurate time to do a four-dimensional B-ultrasound? According to relevant technical personnel,