To investigate the ultrasonoimagedata diagnosis and differential diagnosis of twin pregnancy with one complete hydatidiform mole and coexistent live fetus (CHMCF) and partial hydatidiform mole with live fetus (PHMF), so as to improve the diagnostic accuracy and provide a basis for clinical management of this condition.

Sixteen cases of hydatidiform mole with coexistent live fetus were diagnosed and treated at West China Second University Hospital from January 2016 to June 2021, including 7 cases of CHMCF and 9 cases of PHMF. The clinical manifestations, gestational weeks at ultrasonic diagnosis, ultrasonoimagedata features, and prognosis were analyzed.

All pregnant women with CHMCF had vaginal bleeding, while only 3 pregnant women with PHMF had vaginal bleeding. There was no typical grape-like vesicular echo in the ultrasound images in early pregnancy (6-10 weeks), but no echo, flocculent echo, disorderly echo, or abnormal echo like another gestational sac could be seen near the gestational sac in all CHMCF cases. At 11 weeks of pregnancy, in the cases of CHMCF, the grape-like vesicular echo was limited, and the boundary between the grape-like vesicular echo and the placenta was clear, or the diaphragm-like echo could be seen between the grape-like vesicular echo and the normal fetus. In the case of PHMF, the grape-like vesicular echo was mostly located in the placenta, scattered, or almost occupied the whole placenta. Of all 13 cases of CHMCF, only one patient continued pregnancy to full-term delivery after chromosome examination, and the rest underwent induced labor because of continuous vaginal bleeding, hemoptysis, patient's unwillingness to continue pregnancy, and so on. One case of PHMF developed into gestational trophoblastic neoplasia (GTN), and no GTN or distant metastasis was found in the remaining 12 months of follow-up.

From 6 to 10 weeks of gestation, the ultrasonoimagedata findings of CHMCF and PHMF are not typical, so it is difficult to make a diagnosis. After 11 weeks of pregnancy, a diagnosis or differential diagnosis can be made according to the location of grape-like vesicular echo, its relationship with placenta, and whether there is diaphragm-like echo with the surviving fetus, so as to provide a basis for clinical treatment.