Cervical hydatidiform mole pregnancy after missed abortion presenting with severe vaginal bleeding: case report and review of the literature.

We report a 28-year-old woman presenting with a complete hyaditiform mole localized to the cervix. She had undergone curettage of missed abortion two months previously and the aborted material showed normal placental tissue on histopathologic examination. Two months after curettage she presented with sudden severe vaginal bleeding. Clinical examination revealed a lesion of the epithelial outer surface of the cervix. Due to the bleeding, immediate surgical intervention was necessary. Histological examination revealed a complete hydatidiform mole. Currently, only three cases of this exceedingly rare diagnosis have been published: two reported a partial mole and one a complete hydatidiform mole. In our case, we hypothesize that the pathogenesis took place in two steps. Initially the curettage of the missed abortion damaged the endometrial lining. During a new rapid re-fertilization after the missed abortion, a hydatidiform molar pregnancy developed. Normally this abnormal trophoblast tissue would adhere to the endometrium but in this case we assume that intrauterine implantation was not possible because of endometrial damage at the prior curettage, allowing the abnormal trophoblast tissue to pass the endocervix and emerge into the vaginal vault. Presumably, during the curettage an epithelial defect was produced on the outer surface of the cervix, due to clamping the cervix during dilatation. We speculate that this weak spot on the epithelial surface was responsible for the adherence to the cervix and subsequent bleeding was caused by injury of maternal blood vessels. We propose that careful holding of the cervix with atraumatic clamps during curettage is important to avoid subsequent complications.