Objective Measure fetal brain volume and surface area at specific developmental time points. Several studies describe cerebral cortical development; none attempt to measure this.

Design To allow measurement throughout fetal development specimens at 10.5, 14.5, 16, 19, 24, 28 and 32 weeks gestational age were chosen.

Subjects and Methods The Smith Collection of four fetal specimens and three separate fetal specimens were scanned with permission from the University of Edinburgh Anatomy department. T2 high-resolution MRI scans were performed. Brain volume was measured using the Cavalieri section method and application of stereological methods was used to estimate brain surface area.

Results Fetal brain volume shows a non-linear increase with exponential increase in volume after week 24. Fetal brain surface area shows a non-linear increase with exponential increase in surface area after week 24.

Conclusion Combined with current literature this data confirms that there is a non-linear rate of fetal brain development; the rate of gyri and sulci development corresponds to fetal brain volume and surface area increase. This has clinical implications in assessment and diagnosis of abnormal fetal and neonatal brain development. The data presented here could be used as a baseline for comparison of fetal and neonatal data within a neurological setting, e.g., assessment of brain development in congenital and neonatal brain malformations such as hydrocephalus or ventriculomegaly, congenital infections and assess the impact of acquired conditions such as hypoxic injury, haemorrhage, arachnoid cysts and fetal tumours.