Developmental outcome of isolated fetal microcephaly

To assess the neurodevelopmental outcome of children with prenatally diagnosed isolated microcephaly defined as head circumference more than 2 SD below the gestational mean.

Children aged 2-6 years who had been diagnosed in utero as having head circumference measurements more than 2 SD below the gestational mean were compared with normocephalic children, utilizing a standard neuropsychological battery. Comparisons were also made within the study group.

HCs were between -2 and -4.8 SD, only one fetus having a HC below -3 SD. Children with a prenatal head circumference between 2 SD and 3 SD below the gestational mean did not differ significantly from the control group regarding cognitive, language and motor functioning. However, they exhibited more behavioral-emotional problems. There were no significant differences between children who had suffered from intrauterine growth restriction and those who had not, or between those with familial and those with non-familial microcephaly. Nevertheless, linear regression analysis showed that head circumference in utero helps predict cognitive functioning later in life.

Prenatally diagnosed head circumference between 2 SD and 3 SD below the gestational mean is not a risk factor for later abnormal neuropsychological development.