['This study aims to compare the serum total l-carnitine concentrations of obese and non-obese pregnant women and to identify the role of L-carnitine in both maternal and fetal weight gain during pregnancy.', 'This study reviews 118 healthy women with singleton term pregnancy (≥37 weeks). The characteristics of the recruited subjects were analyzed according to their pre-pregnancy body mass index (BMI).', 'The women with pre-pregnancy BMI\u2009<\u200918.5\u2009kg/m(2) had significantly higher serum L-carnitine levels whereas the women with BMI\u2009>\u200929.9\u2009kg/m(2) at term pregnancy had significantly lower serum l-carnitine levels (p\u2009=\u20090.001 for both). The neonates born to women with BMI\u2009>\u200929.9\u2009kg/m(2) at term pregnancy had significantly longer height and wider head circumference (p\u2009=\u20090.001 for both). Serum total L-carnitine levels correlated significantly and negatively with pre-pregnancy body weight, pre-pregnancy BMI, pregnancy body weight, pregnancy BMI and serum triglyceride levels (r\u2009=\u2009-0.397, p\u2009=\u20090.001; r\u2009=\u2009-0.357, p\u2009=\u20090.001; r\u2009=\u2009-0.460, p\u2009=\u20090.001; r\u2009=\u2009-0.463, p\u2009=\u20090.001 and r\u2009=\u2009-0.216, p\u2009=\u20090.019, respectively). There was a significant and positive correlation between L-carnitine and HDL values (r\u2009=\u20090.243, p\u2009=\u20090.008).'] Are lowered serum total L-carnitine levels associated with obesity at term pregnancy?