Don't medicate the water, unless (A) it's necessary and (B) it's the right medication.
Aquatic meds are generally based on poisons, at a strength strong enough to kill whatever it is that it's aiming at, but weak enough that the fish survive.
For instance, if you try to treat a bacterial infection with an anti-parasitic med, the fish will have the double whammy of suffering from a bacterial infection, and suffering from the anti-parasitic poison which does nothing the get rid of the bacteria. You might think "it's better than nothing", but you'd be wrong - "nothing" is better than "the wrong thing".
In your particular instance, the chances are that it's perfectly normal birthing behaviour, particularly the fact that she has started hiding, but photos or a video would be very helpful.