Case of chronic ectopic pregnancy diagnosed in which the complete shape of the fetus was visible by ultrasonography.

Preoperative diagnosis of chronic ectopic pregnancy is often difficult because of the high incidence of negative results on pregnancy tests as a consequence of the very small amount of live villi, subtle symptoms, and the poor specificity of ultrasonographic patterns. A 45-year-old woman was referred to our department for evaluation of a mass 8 cm in diameter with solid parts in the right adnexal area. Transvaginal ultrasonography showed a mass consisting of a cystic part with an irregular thick capsule distinct from the right ovary. In the center of the cystic part, a fetus-like image, 20 mm in length was seen. Preoperative diagnosis was confirmed by the laparoscopy, which revealed a swollen right tube containing a fetus with highly necrotic changes. This case was unique because chronic ectopic pregnancy was detected at an early stage before absorption of the conceptus occurred, which coincidentally is an appropriate time for morphological diagnosis.