Is it harmful for a fetus to be exposed to loud sounds/drums from a stage performance like drums and banging metallic noises? or do fluids provide enough insulation to muffle the noise?

Harmful!: The developing fetus certainly appreciates loud external noises and the amniotic fluid actually transmits all vibrations very well. Avoid any prolonged exposure of your pregnant belly to loud sounds/noises. It could have untold consequences to your fetus' auditory pathway development and overall well-being. No one is certain about these issues, as research is practically impossible to conduct.