Maternal Bereavement the Year Before or During Pregnancy and Total and Cause-Specific Infant Mortality: A Cohort Study From Denmark and Sweden.

OBJECTIVE

We analyzed the associations between maternal bereavement the year before or during pregnancy and total and cause-specific infant mortality (IM).

METHODS

We studied live singleton births from the Danish (1978-2008) and Swedish Medical Birth Registers (1973-2006; N = 5,114,246). Information on maternal sociodemographic, pregnancy-related, and health-related factors, and death of family members was obtained from nationwide registers.

RESULTS

Among children of mothers with register links to family members and without the considered IM risk factors, 110,993 (2.76%) were exposed and 15,199 (0.4%) died in infancy. Death of an older child the year before or during pregnancy was associated with an increased IM risk (adjusted odds ratio [aOR; 95% confidence intervals {CIs}] = 2.05 [1.44-2.92]). Losing an older child the year before pregnancy or during pregnancy was associated with risks of prematurity-related IM (aOR [95% CI] = 2.61 [1.44-4.72] and 3.08 [1.70-5.57]) and with infant death in term-born children due to causes other than sudden infant death syndrome, congenital malformations, or asphyxia (aOR [95% CI] = 3.31 [1.58-6.96] and 5.10 [1.27-20.43]). Losing an older child during pregnancy was also associated with increased risks of sudden infant death syndrome (aOR [95% CI] = 5.41 [1.34-21.83]). Death of a partner during pregnancy was associated with IM (aOR [95% CI] = 1.83 [1.01-3.32]). The number of events was small and CIs were wide in some subanalyses, and caution is needed when interpreting our results.

CONCLUSIONS

Severe prenatal stress may increase the risk of several types of IM. Whether less severe but more common maternal stressors shortly before or during pregnancy also increase IM risk warrants further investigation.