[Contribution of ultrasonography in the diagnosis of ectopic pregnancy]

High-resolution endovaginal sonography has considerably improved ectopic pregnancy imaging. In conjunction with serum hCG measurements, it allows early detection of ectopic pregnancy (EP) and has significantly reduced the morbidity and the mortality of this disease. The major sonographic finding is the uterine vacuity, the diagnosis of ectopic pregnancy is quite sure in case of absence of intra-uterine pregnancy (IUP) associated with serum hCG above 1500 mUi/ml. Conversely, the presence of IUP excludes practically the diagnosis of EP, but IUP must be distinguished from a pseudosac. The visualization of an ectopic sac that contains an embryo or a yolk sac clearly allows the diagnosis of EP, but its sensitivity is only 25%. The most common sonographic finding is a hematosalpinx, which looks like an echogenic adnexal mass, next to the ovary containing the corpus luteum. Color Doppler is useful to enhance ectopic trophoblastic flow, but it is only a complementary technique of endovaginal sonography. Finally, if the first sonography is inconclusive, a follow-up examination must be performed 2 or 4 days later.