Maternity leave reduces neonatal and infant mortality rates in high-income countries. However, the impact of maternity leave on infant health has not been rigorously evaluated in low- and middle-income countries (LMICs). In this study, we utilized a difference-in-differences approach to evaluate whether paid maternity leave policies affect infant mortality in LMICs.
Methods and Findings
We used birth history data collected via the Demographic and Health Surveys to assemble a panel of approximately 300,000 live births in 20 countries from 2000 to 2008; these observational data were merged with longitudinal information on the duration of paid maternity leave provided by each country. We estimated the effect of an increase in maternity leave in the prior year on the probability of infant (<1 y), neonatal (<28 d), and post-neonatal (between 28 d and 1 y after birth) mortality. Fixed effects for country and year were included to control for, respectively, unobserved time-invariant confounders that varied across countries and temporal trends in mortality that were shared across countries. Average rates of infant, neonatal, and post-neonatal mortality over the study period were 55.2, 30.7, and 23.0 per 1,000 live births, respectively. Each additional month of paid maternity was associated with 7.9 fewer infant deaths per 1,000 live births (95% CI 3.7, 12.0), reflecting a 13% relative reduction. Reductions in infant mortality associated with increases in the duration of paid maternity leave were concentrated in the post-neonatal period. Estimates were robust to adjustment for individual, household, and country-level characteristics, although there may be residual confounding by unmeasured time-varying confounders, such as coincident policy changes.
More generous paid maternity leave policies represent a potential instrument for facilitating early-life interventions and reducing infant mortality in LMICs and warrant further discussion in the post-2015 sustainable development agenda. From a policy planning perspective, further work is needed to elucidate the mechanisms that explain the benefits of paid maternity leave for infant mortality.
Nandi and colleagues, in a large study analyzing data from 20 countries, show that extended, paid maternity leave effectively reduces infant mortality in LMICs.
In 1990, 12 million children—most of them living in low- and middle-income countries (LMICs)—died before their fifth birthday. Out of every 1,000 children born alive, 90 died before they were five years old. In 2000, world leaders set a target of reducing under-five mortality (deaths) to one-third of its 1990 level by 2015 as Millennium Development Goal 4 (MDG4); this goal, together with seven others, was designed to eradicate extreme poverty globally. Over the years, steady progress was made towards MDG4. Better delivery facilities and programs that encouraged breastfeeding, immunization, and other practices that improved the health of young children reduced the global under-five mortality rate. But, by 2015, the rate had only fallen to 43 deaths per 1,000 live births, and 5.9 million children under five died that year from preventable causes such as preterm birth complications, delivery complications, and infections. Nearly half of these deaths occurred among neonates (babies less than 28 days old); three-quarters of them occurred among infants (children less than 1 year old).
Why Was This Study Done?
In high-income countries, paid leave from employment for mothers is associated with reduced neonatal and infant mortality. Many LMICs now have legislation granting paid maternity leave or gender-neutral parental leave. But does paid maternity leave have the same impact on infant health in LMICs as it does in high-income countries? In this quasi-experimental study, the researchers use the difference-in-differences statistical approach to investigate whether paid maternity leave policies affect infant mortality in LMICs. A quasi-experimental study uses observational data to compare outcomes in a group of people receiving an intervention (the treatment group) with outcomes in a group of people not receiving the intervention (control group); unlike a randomized controlled trial, these groups are not chosen at random. The difference-in-differences approach compares the average change over time in an outcome variable (here, infant mortality) in a treatment group (here, babies born in countries with a change—specifically, an increase—in paid maternity leave duration) with the average change over time in the outcome variable in a control group (here, babies born in countries without a change in paid maternity leave duration).
What Did the Researchers Do and Find?
The researchers assembled a panel of about 300,000 live births in 20 LMICs between 2000 and 2008 using birth history data collected by the Demographic and Health Surveys (which collect information on the demographic, health, and other characteristics of a nationally representative sample of households). The researchers merged these observational data with information on the duration of paid maternity leave provided by each country and used the difference-in-differences approach to estimate the effect of an increase in paid maternity leave duration on the probability of infant (<1 year old), neonatal (<28 days old), and post-neonatal (between 28 days and 1 year old) mortality. Average rates of infant, neonatal, and post-neonatal mortality over the study period were 55.2, 30.7, and 23.0 per 1,000 live births, respectively. Each additional month of paid maternity leave was associated with 7.9 fewer infant deaths per 1,000 live births, a relative reduction in infant mortality of 13%. Notably, the reduction in infant mortality with increased duration of paid maternity leave was concentrated in the post-neonatal period.
What Do These Findings Mean?
These findings suggest that policies that increase the duration of paid maternity leave could help to reduce infant mortality in the 20 LMICs included in this study. These findings may not be generalizable to all LMICs. Moreover, their accuracy may be limited by confounding. That is, unmeasured characteristics—rather than changes in paid maternity leave duration—could be responsible for the observed changes in infant mortality. Although the researchers adjusted for many possible confounders in their analysis, there may be some residual confounding from unmeasured time-varying confounders such as other policy changes made during the study period. Further work is now needed to determine the mechanisms that underlie the observed association between increased duration of paid maternity leave and reduction in infant mortality in LMICs. Paid maternity leave might, for example, improve infant health by giving new mothers time to breastfeed, care for ill babies, or ensure that their babies receive their childhood vaccinations. Finally, before LMICs introduce new policies on paid maternity leave, the optimal balance of paid leave from employment before and after delivery needs to be evaluated.
This list of resources contains links that can be accessed when viewing the PDF on a device or via the online version of the article at http://dx.doi.org/10.1371/journal.pmed.1001985.
The World Health Organization (WHO) provides information on child health and child mortality, and on global efforts to reduce child mortality (available in several languages); its 2009 publication Home Visits for the Newborn child: A Strategy to Improve Survival is available
The United Nations Children’s Fund (UNICEF) works for children’s rights, survival, development, and protection around the world; it provides information about the failure to meet MDG4 and a link to a 2015 report on global levels and trends in child mortality; its UNICEF data website provides further detailed statistics about child health and mortality
The Millennium Development Goals 2015 Report is available
The Healthy Newborn Network is an online community of more than 80 partner organizations that addresses critical knowledge gaps in newborn health
Wikipedia has pages on paid parental leave around the world, quasi-experiments, and the difference-in-differences analytical approach (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)