A review.Isotretinoin (ISO) (13-cis-retinoic acid) is a known potent teratogenic drug.Despite the general concept of ISO teratogenicity, the risk of MM secondary to periconceptional exposure to ISO may be lower than originally reported.Actually, the level of beta -hCG in true pregnancy is much higher than in those on beta-hCG diet.In brief, dermatologists should discuss concrete current knowledge to help their patients, who would not opt for pregnancy termination, in their risky decision.Till further studies assess the true risk of ISO-related MM for each trimester, ISO-planned patients have to adhere to the pretreatment counseling programs to reduce the risk of an unplanned or suspected pregnancy.