BACKGROUND Troponin I is the gold standard for the diagnosis of adult acute coronary syndrome. Although it is known that a hypoxic fetus may produce cTnI, fetal cTnI passage in maternal blood has never been documented. CASE REPORT We report a case where the rise of cTnI in the blood of a pregnant woman was not related to maternal heart disease. Instead, it might be suggestive of a fetal cardiac origin, as there was a severe placental insufficiency with a fetal intrauterine growth restriction. CONCLUSIONS This study suggests that the rise of cTnI in maternal blood in a cardiovascular healthy pregnant woman might have a fetal origin. After having excluded any maternal causes, cTnI elevation could be explained with the transfer of fetal cTnI through an injured placenta.