“…Although the topic is highly current, only five publications were found in the systematic literature search that met all our inclusion criteria. Several former studies investigated the role of lipids in oocytes [ 66 , 67 ], early stages of embryo development [ 52 , 56 , 58 , 66 , 68 , 69 , 70 , 71 ], placenta in late pregnancy [ 72 , 73 ], as well as endometrial tissues during the window of implantation [ 74 ], and in endometrial fluid [ 75 ]. However, in these studies, lipid composition was mostly investigated with MS and not with MSI.…”