Preliminary and Incomplete, Do Not Cite Prenatal Nutrition and Adult Outcomes: The E¤ect of Maternal Fasting During Ramadan

We use the Islamic holy month of Ramadan as a natural experiment for evaluating the long-term e¤ects of fasting during pregnancy. Preliminary results using Michigan natality data show that babies of Arab descent who were in utero during Ramadan have lower birthweight compared to those who were not in utero during Ramadan. Using Census data in Uganda we also …nd that Muslim adults who were born nine months after Ramadan are 22 percent (p =0.02) more likely to be disabled. E¤ects are found for vision, hearing, and mental disabilities and may re‡ect neurological impairments from disruptions to early fetal development. We …nd no evidence that negative selection in conceptions during Ramadan accounts for our results. We urge caution in interpreting these results since we cannot directly link the incidence of adult disability with adverse fetal conditions. We thank Ana Rocca, Kenley Barrett and Shyue-Ming Loh for excellent research assistance. We gratefully acknowledge comments from seminar participants at the NBER Cohort Studies Meeting in Salt Lake City, UC Davis, the Harris School, and the Federal Reserve Bank of Chicago. We thank Carlos Dobkin and Janet Currie for extremely helpful suggestions. The views expressed here do not re‡ect the views of the Federal Reserve system.