What is the ruling on making up the days a woman misses fasting due to gastric bypass surgery, and is expiation (kaffarah) required in addition to making them up?

It is permissible for a sick person to break their fast during the day in Ramadan if taking medicine is necessary and delaying it until night is difficult, or if fasting would harm them or delay their recovery. In this case, they only need to make up the fast later.

Vomiting does not invalidate the fast unless it is done intentionally. So, if one is overcome by vomit, they do not need to make up the fast. But if one induces vomiting, they must make it up.

Breaking the fast is legislated for a woman who is sick after surgery and fasting would harm her or be difficult for her. She only needs to make up the fast later. It is preferable to postpone the surgery until after Ramadan.

It is permissible for a person to undergo surgery during the day in Ramadan, even if they could delay it, in analogy to the traveler who is permitted to break their fast.

It is not permissible for a woman to expose her body to a male doctor except in cases of necessity or need, and if no female doctor is available.