[Maternal and fetal retinoid assay. Two case reports of isotretinoin (Roaccutane) exposure].

We report on 2 women who were treated with retinoids (Roaccutan, isotretinoin) during the first trimester of their pregnancies. Therapeutic abortions were carried out. The interest in these case reports lies in the determination of concentration of isotretinoin and its metabolites (4-oxo-isotretinoin, and tretinoin) in foetal tissues, using high performance liquid chromatography. The findings show the significant transplacental passage of isotretinoin, an accumulation of 4-oxo-isotretinoin in the liver, and a low concentration of retinoids in the brain of these foetuses. Contraception must be used with retinoid treatment and for 4 weeks after retinoid withdrawal.