An updated protocol for abortion surveillance with ultrasound and immediate pathology

To modify and improve a protocol for surveillance of patients presenting for routine elective abortion services.

Six hundred seventy-four women presenting for routine elective first-trimester abortions were studied. All were 84 or fewer days after the last menstrual period, had no history of bleeding, and had positive urine pregnancy tests. Each woman was scanned initially with an empty-bladder transabdominal technique. If no sac was seen, endovaginal ultrasonography was performed. All terminations had modified gross examination of tissue (3x magnification) as well as staining for microscopic analysis.

Six hundred twelve patients (90.8%) demonstrated intrauterine gestations on transabdominal ultrasound, 595 of which were 12 or fewer weeks. Suction and sharp curettage and examination of tissue revealed products of conception in all. Seventeen subjects (2.5%) were found to be 13 or more weeks despite bimanual examinations and last menstrual period suggesting 12 or fewer weeks. Sixty-two patients had no sac seen on transabdominal ultrasound, 34 of whom had definitive intrauterine gestations on endovaginal ultrasound. Curettage revealed chorionic villi in all. Two had unruptured definitive ectopic pregnancies seen on endovaginal ultrasound. Twenty-one women with no sac seen on endovaginal ultrasound underwent curettage as the next step in triage; chorionic villi proved an intrauterine gestation in 17. The additional four had decidua only on pathology. Rising hCG levels in two of these four led to a diagnosis of ectopic pregnancy, whereas falling hCG levels in the other two led to a presumptive diagnosis of complete abortion, possibly tubal pregnancy in light of the lack of vaginal bleeding.

Pre-abortion sonography eliminates inadvertent second-trimester cases, and immediate postoperative examination of curettage material expedites the diagnosis of ectopic pregnancy when present.