Concerns from impurities
Level of Concern in Food
A review article reports that this substance is associated with small reductions in infant birth weight.
T. S. Hinds, W. L. West, E. M. Knight & B. F. Harland. 1996. The effect of caffeine on pregnancy outcome variables. Nutrition reviews 54(7), 203-7.
NTP Toxcast scored 0.5-1.5
EWG Toxcast Analysis - National Toxicology Program (NTP)
A peer-reviewed study showed that maternal intake of this substance is associated with low birth weight (moderate to high intake, 2-4 cups).
Verena Sengpiel, Bo Jacobsson, Jan Alexander, Helle Margrete Meltzer, Margaretha Haugen, Ronny Myhre, Jakob Grove, Staffan Nilsson, Jonas Bacelis, Elisabeth Elind & Anne-Lise Brantsæter. 2013. Maternal caffeine intake during pregnancy is associated with birth weight but not with gestational length: results from a large prospective observational cohort study. BMC medicine 11, 42.