The "Yom-Kippur" effect on human parturition

OBJECTIVES: Food withdrawal has been proposed as a possible mechanism for the onset of labor in animals (i.e., sheep) and humans. The proposal is based upon the reported increase in the delivery rate during the Vom Kippur fasting Jewish holiday (JAMA I983;25U:1317). The purposes of this study were I ) to compare the effect of the Yom Kippur fasting between Jewish (study group 1) and Bedouin population (control or not fasting); 2) to determine the diurnal variation of deliveries before, during and after Vom Kippur in both groups; and 3) to investigate the effect of the holidav itself on the rate of deliveries by comparing Yom Kippur to Sukkot. STUDY DESIGN: The .study population consisted of Jewish and Bedouin women who delnered in Soroka Medical Center during the years 198H to 1993. The computerized data of deliveries occurring seven days before Yom Kippur and seven days following Yom Kippur were analyzed. We further analvzed the deliver)' pattern by dniding the Yom Kippur and the day after into four subperiods of six hours each. Time series analysis was conducted to determine the repeated pattern of deliveries along the \ears of the stuch. Data were analyzed using Student's t-test. RESULTS: 1.313 Jewish and 1,091 Bedouin women delnered during the study period. The mean deliver.- rate in the Jewish population was significantly higher during the Yom Kippur and the day after than that occurring before Yom Kippur (15.1 ±5.1 and 14.6 ±4.7 vs. 10.7 ±3.5; p < (1.05, p < 0.01 respectively). No significant changes were noted in the Bedouin population during this period. We found a significant increase in the rate of deliveries during the fourth suhperiod of (he Yom Kippur only. No significant differences were observed in the rate of deliveries during the Sukkot holiday between Jewish and Bedouin women. CONCLUSIONS: Food withdrawal is associated with a significant increase in the rale of term deliven.