We further provide evidence to support the potential mechanism in which choline and betaine modify fetal growth in GDM mice via alterations in placental functioning, such as downregulating the placental growth promoter insulin-like growth factor 2 (Igf2), suppressing the mechanistic target of rapamycin (mTOR) signaling or reducing macronutrient transporter expression [23,24,25]. This evidence concerns the gene IGF2 and gestational diabetes.