Congenital absence of uterus and vagina is a picture known as Mayer-Rokitansky-Küster-Hauser syndrome. Six cases are reported and particular attention is devoted to the anatomical pictures, which can be found in typical or atypical form. Discussion on the etiopathogenetical problems, supporting Hauser’s hypothesis of an inhibition of the müllerian ducts development by MIF production, allows to consider it as the slightest form of female pseudoermaphroditism. Moreover the terms used to delineate this condition, like “müllerian aplasia”, “müllerian ducts aplasia”, “müllerian ducts agenesis” and “uterovaginal agenesis” may be misleading and the term of “müllerian dysgenesis syndrome” is proposed.