Public investments in reducing child mortality may encourage women into greater economic activity. That is the implication of research reported in this column, which finds that improved child survival rates as a consequence of early twentieth century developments in medicine led American women to delay their fertility and stay in the labor market. Fertility and the burden of child mortality in the United States in the 1930s were similar to that in many modern-day developing countries.
The rapid growth in women’s labor force participation was one of the most remarkable economic changes of the twentieth century in developed countries. In the United States, married women’s labor supply grew from 10% in 1930 to 25% in 1950, and it continued increasing at a steady rate until 1990 when it reached 75%. The initial increase has been attributed to increases in high school completion and the growth of office-based jobs, traditionally considered woman-friendly, while the later increase has been associated with advances in home technology, among other factors, including the rise of the feminist movement.
Our research suggests that the decline in child mortality is an additional contributor to this historic trend – one that is likely to be pertinent to understanding demographic and economic change in developing countries today.
Our key idea is that decline in child mortality reduces both the number of children that women desire and the number of children they need to conceive in order to reach their desired number. This allows them to delay fertility and to join or remain in the labor market. The effect is reinforced by the decline in child morbidity, which reduces the time that women, who are often the main caregivers in their families, spend looking after sick children.
As of 2017 in sub-Saharan Africa, the average female labor force participation was 63%. But this average masks significant heterogeneity, with participation ranging from 31% in Mauritania to 83% in Mozambique. We examine the plausibility of our hypothesis by analyzing the relationship between female labor force participation and child mortality.
Countries with lower child mortality tend to have higher female labor force participation. They also have lower fertility as expected, but in contrast to the predictions of economic theory, higher childlessness.
We propose an alternative model, which by integrating fertility timing and labor force participation decisions of women, can explain this result. We test the predictions of this model on early twentieth century data from the United States.
To investigate our hypothesis, we leverage the unexpected and sharp reduction in child mortality created by the introduction of the first antibiotics in the United States in 1937. These were sulfonamide (sulfa) drugs that changed the standard of modern medicine.
The new drugs were used to treat major bacterial diseases including pneumonia, the leading cause of child mortality. A ‘sulfa craze’ followed, with 10% of the US population treated annually by 1941. Mortality rates from pneumonia – which was predominantly a disease of childhood – declined in the United States by 17-32% with the advent of sulfa drugs.
Findings
We find that women reduced their fertility when child survival improved. We document reductions along both the intensive and extensive margins of fertility: women with children had fewer overall and more women remained childless. The effect on childlessness is potentially puzzling, as modern economic theory posits that improvements in child health will make it more – not less – attractive to have at least one child.
This seeming paradox is resolved by understanding that when child survival improves, there is less need to start having children early in life, since each pregnancy is more likely to succeed, and because women may want fewer children overall. Women also need to spend less time caring for sick children. With this increase in disposable time, women can enter or remain in the labor market.
Alternatively, biological factors may limit fertility if it is delayed too long. These circumstances can result in eventual childlessness, even if this was not the woman’s initial intention. Indeed, delay has been proposed as an explanation for the recent rise in childlessness in European countries.
Consistent with the proposed mechanism, we find that after the decline in child mortality caused by the introduction of the first antibiotics, women had children later, were more likely to be in the labor market, achieved better occupations, worked longer hours, and were less likely to have ever been married.
Policy action
Fertility and the burden of child mortality in the United States in the 1930s were similar to that in many modern-day developing countries. Fertility remains high at 4.7 births per woman on average in Africa. Worldwide, pneumonia continues to be the leading infectious cause of death among children, accounting for six million deaths of children under 5 every year. While eighty years have elapsed since the invention of antibiotics, the average consumption of antibiotics in West Africa is approximately 90% lower than in the United States, suggesting poor access.
Our findings imply that public investments in reducing child mortality may reduce the number of pregnancies and encourage women into greater economic activity. Female labor force participation has been argued to encourage long-run economic growth, while the economic empowerment of women has also been associated with greater investment in children and lower domestic violence. But the extent to which this potential is realized will depend on women being able to access work, which is likely to be affected by social norms that constrain women from work.
