Tarry-Adkins JL, et al. - Researchers examined how gestational diabetes mellitus (GDM) treatment affects fetal, neonatal, and childhood growth. PubMed, Ovid Embase, Medline, Web of Science, ClinicalTrials.gov, and Cochrane databases (inception to 12 February 2020) yielded 33 eligible studies (n = 4,944), from geographical locations including Europe, North Africa, the Middle East, Asia, Australia/New Zealand, and the United States/Latin America. In 22 studies (n = 2,801), women were randomized to metformin vs insulin; in 8 studies (n = 1,722), women were randomized to glyburide vs insulin; and in 3 studies (n = 421), women received metformin or glyburide. Eleven studies (n = 2,204) reported maternal outcomes. In all these studies, the weight and growth of their babies in the womb, at birth, or later in childhood were reported. Per analyses, mothers randomized to receive glyburide gave birth to babies significantly heavier at birth compared with those whose mothers were randomized to insulin or metformin. Conversely, babies exposed to metformin are significantly lighter at birth than those whose mothers were randomized to insulin or glyburide. Body composition may also differ at birth among these. Glyburide exposed babies tend to be born larger with elevated fat mass, and metformin exposed babies were born smaller and were thinner, compared with those treated with insulin. As oral anti-hyperglycaemics cross the placenta, their effects on fetal anthropometry could be due to their direct actions on the fetus and/or placenta.