Color Doppler and gray-scale ultrasound evaluation of the postpartum uterus

To evaluate the color Doppler and gray-scale sonographic appearance of the uterus after pregnancy, with special attention to the occurrence of areas of enhanced vascularity and placental remnants.

Cross-sectional observational study involving 385 consecutive women presenting at their first visit after pregnancy. The uterus was evaluated using ultrasound with color Doppler. In the presence of placental remnants, blood was sampled for measurement of beta human chorionic gonadotropin (beta hCG), hemoglobin (Hb) and infectious parameters. If indicated, a dilatation and curettage was performed.

In 8.3% of women, areas of enhanced vascularity were detected with color Doppler examination. Most cases (68.9%) were focal areas of one or more vessels. In 2.6% of patients abnormal vascularity extended over a large area of the whole myometrium. In 6.75% of cases, placental remnants were detected. In 46% of these, blood sampling revealed beta hCG levels below 30 mIU/mL; serological infection parameters and Hb concentration were within the normal range.

Areas of enhanced vascularity of the uterus, ranging from a focal vascular pedicle to a larger area of the myometrium, are relatively common after pregnancy. They are predominantly seen in the presence of placental remnants, in the early postpartum period and after instrumental or manual delivery of the placenta. There are no clear risk factors for retained placental tissue, besides the history of blood transfusion in the early postpartum, and perhaps multigravidity. Serology is of little help in the diagnosis of retained gestational products. The knowledge of the ultrasound and color Doppler features of the uterus after pregnancy may prove of practical value for the management of abnormal uterine bleeding in the postpartum period.