As Jim Heckman and consorts have much emphasized, schooling and labor market outcomes are determined to a large extend very early in life, before school even starts. This puts a considerable burden on mother to provide the right environment for their children, and this is sometimes very difficult for them. With single motherhood or in the absence of sufficient paid maternal leaves, for example, it often becomes impossible to provide a nurturing environment. But one can go back even further. Birth weight is also a very important determinant, and anything that influences it matters.
Douglas Almond, Bhashkar Mazumder and Reyn van Ewijk show that it may not be sufficient to look at the final birth weight but also at how the fetus was nourished on a daily basis. During the month of Ramadan, practicing Muslims fast during daylight, and this includes pregnant women. The analysis shows that Ramadan during early pregnancy is related to lower test scores for the child at age seven. One may think this has to do with cut-off months for school entrance, but the analysis was performed looking at Pakistani and Bangladeshi children in England, thus there is a control population with the same cut-offs and socio-demographic characteristics but no Ramadan observance: Caribbean children. Beyond Muslims, this implies that nutrition is very important in early pregnancy, but this is very difficult to control as pregnancy is not apparent yet. Which means nutrition is important at any time for women in child bearing age.