Nishmat's Women’s Health and HalachaIn memory of Chaya Mirel bat R' Avraham

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Risk of seizures from fasting

21 September, 2003


What should a pregnant woman with a history of grand mal seizures do on Yom Kippur, Tisha B'Av, and other fast days?


Fasts in general have not been shown to cause miscarriages. Thus, for most women, there is no problem with fasting on Yom Kippur or Tisha B Av. Pregnant women do not have to fast on the other fast days.

However, in this case, there is a medical condition. Seizures can be precipitated by fasting. Seizures while pregnant are not good for either the mother or the baby. Such a woman certainly should not fast on the minor fasts. If she is pregnant, she should not fast on Tisha B Av.

On Yom Kippur, she should eat b'shiurim and stay home – regardless of how she feels. The proper procedure is as follows. She should not eat or drink more than a shiur (specific amount) at one time. The shiur for food is  30 cc ( one ounce) lightly packed food. The shiur for liquid is a cheekful (about 40 cc) of fluid. The required interval between them is called "k'dai achilat pras" and has various definitions ranging from 4-9 minutes. Thus, it would be best to eat every nine minutes, but if she feels faint she could make it every four or, in great duress, even two. The food can be eaten in the middle of the nine minutes between drinks, and the drink can be within the nine minutes of the food. Technically, she could continue this all day. However, I would suggest that she repeat the cycle every nine minutes about four times or until she stops feeling light headed, whichever comes later. Later in the day, she repeats the same process. 

All this refers specifically to a situation in which she is pregnant. For the following year, however, she should ask the question again as the situation will be different. During this time, she should consult with a neurologist about the likelihood of her seizures returning.

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