Is it permissible for a pregnant woman suffering from chronic kidney stones to break her fast for days during Ramadan to replenish fluids and take medication, with the intention of completing the fast, fearing the worsening of her health condition and the inability to receive treatment due to pregnancy?

You are permitted to break your fast in Ramadan due to illness (kidney stones that form because of fasting and lack of fluids) and pregnancy, provided that you make up the days later after recovery and childbirth, as Allah Almighty says: "But whoever among you is ill or on a journey [during them] - then [he must fast] an equal number of other days."