Fasting During Pregnancy


Fasting During Pregnancy

Pregnancy and the Four Fasts

Four fasts were decreed by the sages to commemorate critical events in the destruction of the First and Second Temples and the dispersion of Jews into exile. Pregnant women are exempt from fasting on three of these fasts: Tzom Gedaliah, the 10th of Tevet, and the 17th of Tammuz. (They are also exempt from Ta'anit Esther.) There is a difference of opinion as to whether a pregnant woman who feels well should try to fast even though she is not required to. The Rema seems to indicate that the custom is to fast if it is not too difficult for her. However, the Mishneh Brurah states that a pregnant woman who feels any weakness should not fast.

On Tisha B'Av, the anniversary of the actual destruction of both Temples, the halacha requires pregnant women without complications to fast the entire day. Unlike the other fasts, which last from dawn to dusk, the fast of Tisha B'Av is a little over 24 hours long.

It should be noted that not much study has been done on the effect of fasting on pregnancy. One published article showed increased delivery by women the day after Yom Kippur. Another showed an increase during the end of Yom Kippur as well. In both studies, however, most of the deliveries were at term. There is not much evidence that fasting will cause preterm labor, at least in low risk women. Thus, healthy pregnant women should fast.

Some physicians have raised the concern that a woman fasting near term might begin labor dehydrated. Others maintain that, if such a situation were to arise, it could quickly and easily be alleviated by intravenous fluids.

Once a woman is in labor, she no longer has the halachic status of a pregnant woman. She becomes a yoledet and is considered a cholah sheyesh bah sakanah, an ill person who is at risk. A woman in labor is certainly halachically permitted to eat and drink. However, the advisability of eating and drinking during labor is a matter of medical debate, and each woman should consult with her health care provider.

These are general guidelines. Halacha and medicine are both case based. If a woman has some complication of pregnancy she should consult with her physician about his or her concerns with not drinking or eating for 24 hours, and relay these concerns to her rabbi. It is important that the physician be sensitive to the seriousness of this fast and give a well thought out answer.

Pregnancy and Yom Kippur

As opposed to other fasts, Yom Kippur is Torah mandated (Vayikra 16:29 and 23:27). Therefore, the rules of this fast are the strictest of any fast during the year. The halacha requires pregnant women to fast the entire night and day. It should be noted that not much study has been done on the effect of fasting on pregnancy. One published article showed increased delivery by women the day after Yom Kippur. Another showed an increase towards the end of Yom Kippur as well. In both studies, however, most of the deliveries were at term. There is not much evidence that fasting will cause preterm labor, at least in low risk women. Thus, most healthy pregnant women must fast.

Drinking plenty of fluids for a few days before the fast is recommended.

Because fasting on Yom Kippur is a Torah obligation, it takes precedence over attending synagogue. (A woman's fasting on Yom Kippur even takes halachic precedence over her husband's attending synagogue.) If it will help her to keep the fast, a pregnant woman should plan on spending the day in bed, resting and praying on her own.

Fasting during Labor, Childbirth, and Immediately Postpartum

Some physicians have raised the concern that a woman fasting near term might begin labor dehydrated. Others maintain that, if such a situation were to arise, it could quickly and easily be alleviated by intravenous fluids.

Once a woman is in labor, she no longer has the halachic status of a pregnant woman. She becomes a yoledet and is considered a cholah sheyesh bah sakanah, an ill person who is at risk. A woman in labor is certainly halachically permitted to eat and drink, even on Yom Kippur. However, the advisability of eating and drinking during labor in general is a matter of medical debate, and she should consult with her health care provider.

A woman maintains the status of yoledet for the first week after childbirth. If she gives birth within three days before Yom Kippur she is not allowed to fast. If she gives birth 4-7 days before, she can only fast if she feels up to it and her health care provider does not object. The exact calculation of these time periods is a matter of halachic debate (whether 24-hour days, or nightfall to nightfall). Therefore, in borderline situations, a specific halachic question should be asked.

Shiurim (Minimum Quantities)

The prohibition against eating or drinking on Yom Kippur extends even to tiny amounts. However, the penalty for violating this prohibition applies only if a certain quantity (shiur) of food or drink is consumed. Therefore, one for whom fasting is dangerous may sometimes be instructed to eat or drink less than a shiur at one time.

The shiur for drinking is half of one mouthful (measured before the fast by filling the mouth and cheeks with liquid, emptying it into a measuring cup, and halving that). If eating is necessary, a woman may eat up to 30cc at a time. Ideally, these quantities should be consumed at intervals of at least nine minutes; however, opinions vary and some authorities permit intervals as short as four minutes. A woman who needs to break her fast should have in mind while eating that she is fulfilling the mitzvah of "vechai bahem", living for the sake of Torah (and not risking life).

These are general guidelines. Halacha and medicine are both case- based. If a woman has some complication of pregnancy she should consult with her physician about his or her concerns with not drinking or eating for 24 hours, and relay these concerns to her rabbi. It is important that the physician (even if not religious or non-Jewish) be sensitive to the seriousness of this fast and give a well thought- out answer.

Halachic Sources

Shulchan Aruch, Orach Chaim 549, 541:1, 554:3 & 5
Talmud Bavli, Pesachim 54b

Medical Sources

Kaplan M, Eidelman A, Aboulafia Y. Fasting and the precipitation of labor. The Yom Kippur effect. JAMA 1983; 250:1317-18.

Wiser A, Maymon E, Mazor M, Shomn-Vardi I, Silberstein T, Wiznitzer A, Katz M. Effect of the Yom Kippur fast on parturition [Heb]. Harefuah 1997; 132: 745-48, 824]

Sluetal M, Golden SS. Fasting in labor: relic or requirement. J Obstet Gynecol Neonatal Nursing 1999; 28:507-12).

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