How can I make up for the missed days of Ramadan, knowing that I am currently pregnant and breastfeeding, and what is the legal ruling if my breast milk decreases due to fasting in the coming Ramadan?

Days missed in Ramadan (definition) due to pregnancy must be made up before the onset of the next Ramadan. If making them up is not possible due to a valid excuse until the next Ramadan begins, there is no sin, and they should be made up afterward. However, if the delay is without a valid excuse until the onset of the next Ramadan, then making them up is obligatory along with expiation (kaffarah (definition)). If a pregnant or nursing woman cannot fast in Ramadan out of fear for her child, she is permitted to break her fast and make up the days later, and according to the most authoritative opinion, there is no expiation required of her.