"We use the Islamic holy month of Ramadan as a natural experiment for evaluating the long-term effects 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 find that Muslim adults who were born nine months after Ramadan are 22 percent (p =0.02) more likely to be disabled. Effects are found for vision, hearing, and mental disabilities and may reflect neurological impairments from disruptions to early fetal development. We find 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"--Federal Reserve Bank of Chicago web site.