CALB2 and fetal growth restriction: Here, we aim to determine whether IUGR induced via chronic placental insufficiency (CPI) in the pregnant guinea pig, a long gestation species with an intrauterine neurodevelopmental timeline similar to humans (see review by Morrison et al., 2018), affects early originating, COUP‐TF interacting protein 2 (Ctip2)‐IR subcortical excitatory projection neurons, and two subclasses of GABAergic inhibitory interneurons—somatostatin (SST)‐IR and CR‐IR.