Maternal drug or alcohol abuse is associated with decreased head size from mid-pregnancy to childhood.

Aim: Maternal alcohol abuse is poorly recognised and causes developmental problems. This study explored the foetal central nervous systems (CNS), head circumference and psychomotor development of children exposed to drugs or alcohol during pregnancy up to 2.5 years of age.

Methods: We recruited 23 pregnant women referred to Kuopio University Hospital, Finland, by their family doctor because of drug or alcohol abuse, and 22 control mothers. Foetal CNS parameters were measured by three-dimensional ultrasonography at the mean gestational age of 20 weeks and the Griffiths Mental Developmental Scales (GMDS), and anthropometric measurements were carried out at the mean ages of one and 2.5 years.

Results: The exposed foetuses had decreased biparietal and occipito-frontal distances and head circumferences, but unchanged cerebellar volume at 20 weeks, and decreased head circumferences and length and height at birth, one and 2.5 years of age. They scored lower than the controls on the GMDS general quotient and the hearing, language and locomotor subscales at 2.5 years of age.

Conclusion: Maternal alcohol or drug exposure was associated with decreased head size from mid-pregnancy to childhood and reduced development at 2.5 years. Foetal head circumference at mid-pregnancy was a useful indicator of substance abuse affecting the CNS.