Analysis of transabdominal ultrasonic findings of 167 patients presented with clinical suspicion of extrauterine pregnancies (EUP), all with measurable serum HCG, has been undertaken. Patients were divided into two main groups, namely those with demonstrable typical intrauterine gestational sac (46.7%), and those without (53.3%). This later group of patients, i.e., without intrauterine sac, was further subdivided into four other groups depending on whether or not they have adnexal mass and/or fluid in cul-de-sac. In this first subgroup of patients (21 cases), without any demonstrable mass or fluid, a positive predictive value (PPV) for EUP of only 28.6% was obtained. With ultrasound showing fluid but no mass, the PPV was 55.6%, while those with both mass and fluid, the PPV as high as 95.7% was possible. Characterization of the adnexal mass or cul-de-sac findings among those with empty uterus may further improve PPV. The results of this study indicates that ultrasonic examination can help to provide a more correct diagnosis in the investigation of EUP. EUP can be easily excluded, in the great majority of cases, with sonographic visualization of intrauterine pregnancy. In the case of empty uterus with no mass or fluid, patients should be closely followed up with HCG titer and ultrasonic examination. For those with empty uterus with fluid, culdocentesis may be indicated; whereas in the case of empty uterus with mass, laparoscopy should be considered as additional investigative procedures.