Background Intrauterine growth restriction (IUGR) has been related to neurodevelopmental and learning disabilities. Only undernutritional models have been used to study these alterations. It is thought that uterine ischaemia models might reflect better what is happening in human pregnancies in developed countries. The objective of this project was to study the consequences on the learning and memory process in IUGR pups induced by uterine ischaemia.
Methods IUGR was induced by two meso-ovarian vessel cauterisations in pregnant rats on day 17. Sham surgery was performed in control animals. All deliveries were at term. All the pups were divided into three groups: control (G1; n = 15); IUGR (G2 birth weight <2 ST; n = 15) and ischaemia without weight repercussion (G3; n = 15). From day 25 of life, all of them performed an aquatic learning test during 15 days.
Results The results of the test allow us to distinguish between three learning phases: adaptation (1), learning (2) and stabilisation (3). Analysis of the results shows differences in the learning phase between controls and both IUGR and ischaemia groups (p = 0.0041). No differences were detected in phases (1) or (3). No differences in errors were detected between ischaemia and IUGR, and both performed better than controls (57.14%). No sex differences were detected.
Discussion Learning and memory disabilities were observed in those affected by IUGR. These differences were also seen in those animals of the same litter but without weight restriction (ischaemia). Although ischaemia may not lead to IUGR, central nervous system development and skills may be affected.