Dear Rabbi Simon,
Under what circumstances is a pregnant woman permitted to drink or eat during the fast of Yom Kippur? My wife is in her first trimester and has been having dry heaves/nausea over the last few days and I was wondering what kind of latitude we had under her circumstances.
The accepted practice is that pregnant women who are otherwise healthy do fast on Yom Kippur. Nevertheless, as you know the halakha is very scrupulous with regard to the possibility of piku’ah nefesh and therefore if there is any possibility of harm to the fetus, your wife may definitely eat “shiurim”, i.e. 30 cc of food and 40cc of fluid every 9 minutes. If necessary, she may eat/drink at more frequent intervals too, e.g. 8, 7 or 6 minutes.
In the absence of a doctor to instruct her to eat, your wife will have to judge for herself how awful she feels, to justify breaking her fast, as per the above. In any case, she should definitely stay home and rest (and hopefully not have to drink/eat) rather than go to shul, etc, if that may necessitate her drinking as a result.
I hope this is helpful, and sufficiently clear.
All good wishes for 5769!