Batra NA, Seres-Mailo J, Hanstock C, Seres P, Khudabux J, Bellavance F, Baker G, Allen P, Tibbo P, Hui E, Le Melledo JM. Proton magnetic resonance spectroscopy measurement of brain glutamate levels in premenstrual dysphoric disorder. Biol Psychiatry 2008;63(12):1178-84. 2008.
McEwen AM, Burgess DT, Hanstock CC, Seres P, Khalili P, Newman SC, Baker GB, Mitchell ND, Khudabux-Der J, Allen PS, Le Melledo JM. Increased glutamate levels in the medial prefrontal cortex in patients with postpartum depression. Neuropsychopharmacology 2012; 37(11):2428-35.
Kim P, Leckman JF, Mayes LC, Feldman R, Wang X, Swain JE. The plasticity of human maternal brain: longitudinal changes in brain anatomy during the early postpartum period. Behav Neurosci 2010;124(5):695-700.
Little is known about the cerebral changes associated with pregnancy. Without information on the normal brain alterations associated with pregnancy, it is difficult to investigate the brain mechanisms responsible for the impact of pregnancy on mood, either directly during pregnancy or indirectly during the postpartum period. The aim of this study was to investigate glutamate (Glu) levels in the medial prefrontal cortex (MPFC) during late pregnancy in healthy controls using 1H-Magnetic Resonance Spectroscopy (MRS). Twenty-one healthy pregnant women without any current or past psychiatric diosrder (pregnanct HCs: pHCs) and fourteen non-pregnant health controls without any current or past psychiatric disorder underwent 1H-MRS scans 2 - 3 weeks prior to delivery of pHCs and during the follicular phase of the menstrual cycle for non-pregnant health controls (FPHCs). Metabolites and tissues composition were measured in the MPFC of pHCs and FPHCs. MPFC Glu levels were decreased in pHCs vs FPHCs (6.74 +/- 1.55, 8.53 +/- 1.55, p=0.001, p<0.0001 respectively). However, the % in Grey Matter (%GM) were also decreased in pHC women vs FPHC women (46.53 +/- 10.66 vs 60.43 +/- 6.98, p<0.0001). After correction for %GM (ANOVA), the difference in Glu levels lost its statistical significance (p=0.11). There have been no previous investigations of changes in tissue composition in the brain of pregnancy women. Glu is mainly found in GM which explains the loss of statistical significance when changes in %GM were taken into consideration. This decrease in % of GM may relate to the transitory self-report of decreased cognitive ability by pregnant women (pregnesia).