What is the first action to take in preventing hypotension in a pregnant client?

Repositioning the client is the first action to take in preventing hypotension during pregnancy, particularly when considering the effects of weight and pressure from the uterus on major blood vessels. When a pregnant client is positioned flat on her back, the enlarged uterus can compress the inferior vena cava, which may lead to decreased venous return and cause hypotension. By repositioning the client to a left lateral position, the pressure on the vena cava is alleviated, enhancing blood flow back to the heart and ultimately improving maternal blood pressure.

While providing oxygen, increasing IV fluids, or calling the healthcare provider may be important subsequent actions, they do not directly address the immediate mechanical factor contributing to hypotension in this scenario. Repositioning is a quick, effective, and non-invasive first step that can stabilize the client and prevent further complications associated with hypotension in pregnancy.