Second-trimester vaginal bleeding: correlation of ultrasonographic findings with perinatal outcome

Our purpose was to determine the relationship between ultrasonographic findings and perinatal outcome in patients with second-trimester vaginal bleeding.

A retrospective case-control study was performed. One hundred sixty-seven patients with ultrasonographic examinations performed for bleeding between 13 and 26 weeks' gestation were identified through a comprehensive ultrasonography database. The main ultrasonographic findings of interest were the presence of an intrauterine clot, membrane separation, and placenta previa. A control group of 167 patients was obtained by selecting the next consecutive patient from the comprehensive perinatal database. Perinatal outcome measures for both groups were recorded.

Multiparity was more common in patients with bleeding than in controls (69% vs 58%, p = 0.036), as was history of two or more previous preterm deliveries (6% vs none, p = 0.005). Second-trimester vaginal bleeding was associated with increased risk of preterm delivery (relative risk 1.9, 95% confidence interval 1.4 to 2.8), fetal death (relative risk 6.3, 95% confidence interval 1.9 to 2.1), and perinatal death (relative risk 5.4, 95% confidence interval 2.1 to 13.7). The perinatal mortality rate was 162:1000 in these patients versus 30:1000 in controls. To assess the impact of ultrasonographic abnormalities, the study group was divided into two groups. Among the patients with second-trimester vaginal bleeding those with abnormal ultrasonographic findings had an increased risk of preterm delivery (relative risk 2.0, 95% confidence interval 1.4 to 2.8), fetal death (relative risk 2.6, 95% confidence interval 1.1 to 6.3), perinatal death (relative risk 2.6, 95% confidence interval 1.3 to 5.3), and neonatal intensive care unit admissions (relative risk 3.2, 95% confidence interval 1.6 to 6.1). The perinatal mortality rate was 258:1000 for patients with abnormal ultrasonographic examinations.

Second-trimester vaginal bleeding is more common in multiparous women and in women with a history of a previous preterm delivery. Perinatal morbidity and mortality is increased in patients with bleeding during the second trimester. The risk is compounded when abnormalities are detected by ultrasonography.