Hysterosalpingography and selective salpingography in the differential diagnosis of chemical intrauterine versus tubal pregnancy.
OBJECTIVE: To determine the validity of hystersalpingography (HSG) and/or bilateral selective salpingography in the differential diagnosis of early (biochemical) intrauterine versus intratubal abortions. DESIGN: The study design involved the performance of HSG and selective salpingography in sequential patients with low declining beta-human chorionic gonadotropin (beta-hCG) values. SETTING: Medical School-affiliated Infertility Center. PARTICIPANTS: Four sequential pregnant infertility patients who demonstrated declining beta-hCG levels before pregnancy could be confirmed by ultrasound (chemical pregnancies). RESULTS: Three of four patients demonstrated a characteristic tubal opacification pattern in conjunction with a normally appearing endometrial cavity, considered diagnostic of an early tubal pregnancy. In contrast, a missed intrauterine pregnancy (IUP) demonstrated a characteristically abnormal endometrial cavity. CONCLUSIONS: Some early (chemical) pregnancy losses are intratubal rather than intrauterine. The correct differential diagnosis of early missed IUPs versus intratubal pregnancies is important because of its prognostic significance.