Prenatal stress and cerebral palsy: a nationwide cohort study in Denmark.

OBJECTIVES

Exposure to prenatal stress may affect neurodevelopment of the fetus, but whether this exposure increases the risk of cerebral palsy (CP) later in life is unknown. We aimed to examine the association between maternal bereavement during the prenatal time period and CP in childhood.

METHODS

We conducted a nationwide cohort study by linking information from nationwide registers. All 1,501,894 singletons born in Denmark from 1979 to 2004 were followed up from birth to the end of 2006. We identified 39,601 children whose mothers lost a close relative (child, spouse, parent, sibling) during pregnancy or up to 1 year before pregnancy and they were classified as the exposed group. The outcome of interest was the diagnosis of CP as registered in the National Hospital Register. We used Cox Regression to estimate the hazard ratios (HRs).

RESULTS

Exposure to maternal bereavement after the loss of a child during the prenatal period was associated with an increased risk of CP among children born preterm without intrauterine growth retardation (HR 2.26, 95% CI, 1.09-3.79) and among children born at term with intrauterine growth retardation (HR 2.01, 95% CI, 1.04-3.89). Prenatal stress after maternal bereavement by loss of other relatives was not associated with an increased risk of CP.

CONCLUSIONS

Our data suggest that extremely severe stress in prenatal life could increase the susceptibility for CP among children born preterm or with impaired fetal growth.