Meconium is the earliest stools of newborn. It starts forming from the 13th week of gestation in intestinal contents and accumulates until birth. Usually, it is expelled by the newborn between 24 and 48 hours after birth. This complex matrix has the advantage to integrate a large period of exposure of the foetus to xenobiotics while urine and blood only represent a short-term exposure. This work presents analytical consideration for the detection and the quantification of volatile aromatic compounds (VOCs): BTEX (benzene, toluene, ethylbenzene and xylene) and chlorinated solvents (trichloroethylene and tetrachloroethylene) in meconium. This biological matrix is very viscous and sticky, very difficult to manipulate and homogenize. To analyze VOCs, a headspace analysis method avoiding laborious sample preparation due to the complexity of meconium was selected. Analyzes were then carried out by HeadSpace Solid Phase MicroExtraction (HSSPME) coupled with Gas Chromatography coupled to Mass Spectrometry (GC/MS). As meconium is a rare and heterogeneous matrix from one infant to the others, matrix calibration is difficult to perform. This work has investigated if calibration in water could be used for quantification of target components. The addition of isotopic labelled internal standard for each of the target compounds has allowed a correction of these differences when ratio of standard on internal standard is applied. External and internal calibrations were compared in these two matrices. It was particularly studied if the correction with isotopic labelled internal standards is adequate to use an internal calibration in water to quantify molecules in meconium (it contains 70% of water). Influence of the matrix was observed on the response obtained with a significant decrease in amount of molecule, adsorbed on the fibre, when comparing sampling using meconium and water. The results have shown that the quantification by external calibration is less reliable than the internal calibration in these matrices. It also appears that the correction with isotopic labelled internal standards is not enough to allow the transposition of internal calibration in water to quantification in meconium for all target compounds. Analyzes of meconium were carried out with an internal calibration in meconium for BTEX and chlorinated solvents. The limit of quantification was 80 pg/g for most of the compounds