Final answer:
Leopold's maneuvers are used to estimate fetal weight and clinically evaluate fetal presentation and position. They are a manual clinical assessment technique, distinct from imaging studies like ultrasounds which are the safest for monitoring fetal development during pregnancy.
Step-by-step explanation:
The method used to estimate fetal weight and clinically evaluate fetal lie, presentation, position, and attitude is Leopold's maneuvers. These maneuvers are manual techniques performed by a healthcare provider to determine the position of the fetus inside the uterus. This clinical assessment is significant for planning of labor and delivery. It differs from imaging studies and tests such as the Non-Stress Test (NST), Biophysical Profile (BPP), or Contraction Stress Test (CST), which are used to assess fetal well-being but do not provide physical manipulation for fetal assessment.
Regarding the safest imaging study to use during pregnancy, ultrasounds are considered the safest option because they do not use ionizing radiation, which can be harmful to the developing fetus. Ultrasounds are commonly used to monitor the development and position of the fetus throughout pregnancy.