Infant-feeding practices and infant survival by familial wealth in London, 1752-1812.

Anecdotal evidence indicates that high-status women in England generally did not breastfeed their children in the seventeenth and early eighteenth centuries. Metropolitan families of varied social status also often sent their children out of London for wet-nursing. However, anecdotal sources and rural burial registers also suggest that these practices declined rapidly from the mid-eighteenth century, and were replaced by a culture of maternal breastfeeding in all social classes. These changes in infant-feeding practices have been argued to explain much of the dramatic improvement in infant mortality rates in London in this period. Here we used quantitative evidence from a partial family reconstitution of the London parish of St. Martin in the Fields to test these claims. Using birth interval analysis to infer breastfeeding patterns in families by four categories of wealth, we found that birth intervals were close to the national average in pauper and poor families, but much shorter in wealthier families, in the period 1752-74. We also found evidence that many infants especially in wealthier families were missing from observation, consistent with high levels of rural wet-nursing. Both these phenomena declined between 1775 and 1812, suggesting a convergence in breastfeeding practices to the national norm. We used event history analysis, with corrections to aggregate rates for missing infants, to compare mortality rates over time and by wealth category. We found that infant mortality was initially higher in wealthier families, but declined in all groups over the period 1752-1812. We conclude that increases in maternal breastfeeding were probably important in improving survival of infants from wealthier families, however changes in breastfeeding patterns were insufficient to account for the ubiquitous improvements in mortality of urban-born infants in this period.