What are the harmful effects of body fat scales on the human body?

During pregnancy, people with pacemakers, artificial dialysis, other transplant medical equipment, and edema should avoid using body fat scales as much as possible. The Xiaomi body fat scale uses the BIA bioelectrical impedance method. When standing on the body fat scale, a weak alternating current will pass through the body. Since pregnant women have higher requirements for the internal and external environment, it is not recommended to use it.