Adverse Maternal Metabolic Intrauterine Environment and Placental Epigenetics: Implications for Fetal Metabolic Programming

Purpose of Review: Herein, we summarize existent epidemiological studies relating adverse maternal metabolic environments of maternal obesity and gestational diabetes and placental DNA methylation. Recent Findings: Multiple studies have evaluated associations between intrauterine exposure to gestational diabetes and/or maternal glucose levels and DNA methylation at candidate metabolic genes as well as in epigenome-wide studies. Some of the genomic regions more consistently associated include lipid-related genes (LPL and PPARGC1A), the major histocompatibility complex (MHC), and imprinted genes. Studies solely focused on maternal obesity influences on the placental epigenome are scarce. Summary: Understanding the placental mechanisms involved in fetal metabolic programming could lead to discovery of placental biomarkers at birth that predict later-life metabolic risk. Moving forward is important to standardize methods utilized in epigenetics research; consistent methodology can help interpret disparate findings. Larger studies with longitudinal follow-up are needed to address future challenges in fetal programming research.