1. How long does it take to do a B-ultrasound during pregnancy? Pregnancy is a very important process in a woman\’s life, and B-ultrasound is one of the important means to detect fetal health. So, how long does it take to do a B-ultrasound during pregnancy? Under normal circumstances, it is recommended to conduct the first B-ultrasound examination around 8-12 weeks of pregnancy. At this time, the development and number of the fetus can be preliminarily determined, and diseases such as ectopic pregnancy can be ruled out. 2. How long does it take to tell the gender of the fetus during pregnancy? Many expectant parents are very concerned about the gender of their future baby.