Growth before birth: the relationship between placental weights and infant and maternal health in early-twentieth century Barcelona

Although a number of writers have argued that birth weights have increased in different parts of the world over the last 150 years, others have disputed this. The absence of clear evidence of increasing birth weights contrasts with the picture provided by child and adult heights and raises profound questions about the measurement of changes in intrauterine health. This article uses newly discovered data from Barcelona's Provincial House to examine the extent to which placental weights, and the ratio of birth weight to placental weight, can help to fill this gap. We find some evidence to suggest that there was an inverse relationship between placental weights and male real wages in Barcelona between c. 1908 and 1920. We also show that both low placental weights and high placental weights were associated with adverse birth outcomes. However, after reviewing a large number of different studies, we do not find any clear evidence of an unequivocal trend in placental weights over time. Our results also have implications for our understanding of the impact of the First World War on the standard of living in non-combatant countries and its long-term effects on those who were born during the conflict.