Siman 617

Pregnant and nursing women fast and complete the fast on Yom Kippur like all other people. And even on Tisha B'Av the law is so, as I wrote in siman 554, because there is no danger in them fasting, unless they are ill regardless, and their law is like all the ill that will be explained in the next siman. However, a pregnant woman who smelled the scent of food, for the fetus smells and she craves this, and if she does not eat—both are endangered (Rashi 82a). And from where do we know that it is so? For example, if her face changed, even though she did not say "I need." Or if she said "I need," even though her face did not change (Magen Avraham subsection 1). And any other healthy person, when he says "I need," if his face did not change—it is impossible to believe him without a doctor (ibid.). And it is also clear that when one reaches such a level—his face will change. But the pregnant woman is believed even without the change of the face, because this is common in a pregnant woman.

A pregnant woman who smelled [food], as I have written – one whispers in her ear that today is Yom Kippur. If her mind was put at ease, and she says that the craving has been removed from her, as we find such stories in the Gemara there – it is well. But if her mind was not put at ease – one feeds her until her mind is settled. And one feeds her less than the shiur at a time, as will be explained in the next siman regarding a sick person. However, if according to appearances it is not sufficient for her, and she is compelled to eat much at once in order to remove the craving – one feeds her much.

And so too any person who smelled the scent of good food and his face changed, and this is bulmus, and he may be in danger if they do not give him from the food – they likewise give him less than the shiur, for presumably it will suffice for him. And if it does not suffice – they give him all his needs. And more will be explained regarding this in the next siman. And know that sometimes a pregnant woman is satisfied with a mere taste. Therefore, first they dip something for her into the broth and place it into her mouth. If she is satisfied – it is well. And if not – they go back and give her from the broth. And if even this does not suffice – they give her from the food itself (see Magen Avraham, subsection 2).

A woman who has given birth within three days, even if she is healthy and says she does not need to eat—it is forbidden for her to fast, for it is established by the sages that she will be endangered by her fasting. However, they feed her less than the shiur at a time. And from three until seven days—they are not equal in their nature: there are those who can endure the fast without any damage to the body, and there are those who cannot. Therefore, it depends on her: if she says "I need to eat"—they feed her. And if she said "I do not need"—they leave her to fast. And they ask her opinion, and she answers "yes" or "no." And in our time, it is known that they themselves will always say that she does not need, and it is impossible to rely on this. Therefore, if there is a doctor—they shall ask the doctor. And if not—the expert women shall say. And if there is a doubt—they feed her less than the shiur at a time, for in a doubt regarding lives one is lenient. And from seven days and onward—she is like a sick person who is not in danger, and her law is like other illnesses that will be explained. (What the Korban Netanel wrote in the chapter "Mefanin" to reject the words of the Tur and the Shulchan Aruch based on the words of the Rosh there—is not a difficulty at all. For this is not a comparison, as regarding eating only she knows. But regarding the needs of a woman who has given birth, they know. Examine carefully and you will find it easy.)

These days are not counted from hour to hour. For example, if she gave birth on the seventh of Tishrei in the evening—one does not feed her on Yom Kippur unless she said, "I need to." And even though three days were not completed for her until the evening of Yom Kippur, nevertheless, since Yom Kippur is the fourth day of her giving birth—her law is like after three days. For all natural matters follow this path.