[Prenatal diagnosis in dermatology: contribution of the ultrastructural study].

Fetoscopy and fetal skin biopsy have together played an important role for antenatal diagnosis of various hereditary skin disorders (genodermatoses). The fetus and placenta can be visualized directly and skin biopsy samples can be obtained for light and electron microscopic studies, tissue culture and biochemical analysis. These techniques have been used successfully in the prenatal diagnosis or exclusion of some types of epidermolysis bullosa, ichthyosis, Chediak-Higashi syndrome, oculocutaneous albinism and anhydrotic ectodermal dysplasia in fetuses known to be at risk from these diseases. The purpose of this report is to describe the current methods of fetoscopy and fetal skin biopsy and to review their main dermatological indications. Complications associated with these procedures are also discussed.