In utero exposure to coumarin derivatives may affect the development of the
central nervous system of the child, irrespective of the period of exposur
e in pregnancy. Little is known about effects on development in the long te
rm. The aim of the present study was to determine whether prenatal exposure
to coumarins affects behavioural outcome in children at school age, Behavi
oural outcome was assessed in a cohort of 305 exposed children, aged 7-15 y
ears. Findings were compared with those in a cohort of 263 non-exposed cont
rols, matched For sex, age, and demographic region. Behaviour was rated by
parents and teachers using standardized questionnaires: the Groningen Behav
iour Checklist Family situation (GBF) and the Groningen Behaviour Checklist
School situation (GBS), respectively. The findings of the GBF were support
ed by the results of the GBS, Filled in by teachers who were blind for the
exposure status of the child. In comparison to the non-exposed children, th
e coumarin-exposed children scored lower on the cluster 'positive task orie
ntation' (GBF P < 0.05, GBS P < 0.01), they scored higher on 'emotional ins
tability' (GBF P < 0.001, GBS P < 0.05), and they had more problems on the
social clusters (P < 0.01). Based on the results of both questionnaires, we
conclude that behavioural development may be negatively influenced in scho
ol-age children after in utero exposure to coumarins, leading to less favou
rable task-oriented and social-emotional behaviour. However, the frequency
of clinically relevant 'problem behaviour' (GBF) was not increased in relat
ion to coumarin exposure, the odds ratio was 1.2 (CI95 0.7-1.8). (C) 2000 E
lsevier Science Ireland Ltd. All rights reserved.