Maternal hypertensive disorders during pregnancy and mild cognitive limitations in the offspring.

BACKGROUND

It remains unclear whether maternal hypertensive disorders could impact cognitive development of the child. The aim of this study was to explore the association between hypertensive disorders and other maternal biological and social factors on the risk of mild cognitive limitations (intelligence quotient 50-85) in the offspring.

METHODS

An 11.5-year follow-up study of the Northern Finland Birth Cohort 1986 (n = 9432) was utilised. The analysis included 8847 singleton children, of whom 198 had mild cognitive limitations. Gestational hypertension was defined as de novo hypertension (blood pressure ≥ 140/90), diagnosed mid-pregnancy in a previously normotensive woman. Data on intelligence level of the children were based on standardised intelligence test results.

RESULTS

Eleven per cent (n = 20) of mothers having a child with mild cognitive limitations had gestational hypertension. Maternal gestational hypertension was independently associated with increased odds of mild cognitive limitation in the offspring (odds ratio 2.4 [95% confidence interval 1.4, 3.9]). Other independent maternal risk factors for mild cognitive limitation were high pre-pregnancy body mass index (≥30 kg/m(2)), multiparity (≥4) and low education. In addition family's socio-economic status lower than professional, male gender and small birthweight-for-gestational age appeared as independent risk factors for mild cognitive limitation.

CONCLUSIONS

Gestational hypertension should be considered as one of the adverse early risk factors that may predispose to impaired cognitive development in childhood.