Possible conversion to choriocarcinoma after hydatidiform mole is denoted by all of the following, except:-

Pre-disposing factors for development of choriocarcinoma after molar pregnancy - Rising hCG >100,000 Increased uterus size >6 cm Theca-lutein cysts * Sub urethral nodule indicates vaginal metastasis from choriocarcinoma ,it is not a predisposing factor. * Do not try to biopsy the sub urethral nodule it will result in torrential hemorrhage.