A case of focal severe atypical hyperplasia-carcinoma in situ discovered during voluntary abortion is described. The patient did not undergo hysterectomy; after abortion, menses were regular and the endometrium was histologically normal at a control. Ten cases of endometrial epithelial neoplasia in pregnancy (9 cases) or in puerperium (1 case) found in the literature were reviewed. Although in some of them stromal invasion, which actually is the main prognostic indicator of endometrial neoplasia, was absent or not documented, all lesions were designated as adenocarcinoma. There is evidence that young women with a noninvasive neoplasm and desiring children or preservation of the uterus may be treated conservatively even if the lesion is detected in pregnancy or puerperium.