Well... you're not supposed to lift anything heavy when pregnant in the latter stages- so use smaller containers or a hose to refill. Get hubby to haul the water out.
And... you may need to stand sideways to the tank when cleaning it when you get to the 9th month.
... and if you get cravings for fish, shrimp, or snails... STEP AWAY FROM THE TANK!
women in southeast asia have been pregnant and giving birth while working in the rice patties for centuries with relatively no problems.
I would say a nice home aquarium is going to be WAAAAAY cleaner than that.