Objective: To evaluate whether vasa previa at delivery is associated with a history of second-trimester placenta previa.
Study design: Retrospective, case-control study of all vasa previa cases at Good Samaritan Regional Medical Center from January 1, 1991, to May 1, 2001. Cases were identified by ICD-9 codes and confirmed by chart review. Each case was matched in a 1:4 ratio with controls based upon normal placentation at delivery, ultrasound documentation of midtrimester placental location, maternal parity and gestational age at delivery.
Results: During the study period, 13 cases of vasa previa were identified. Nine cases (9/13, 69.2%) of vasa previa at delivery had a second-trimester placenta previa as documented by midtrimester ultrasonography, whereas 2 controls (2/52, 3.8%) had a second-trimester placenta previa (P < .000001, OR = 56.3, 95% CI = 8.9-354.1).
Conclusion: There is a highly significant association between vasa previa at delivery and a history of second-trimester placenta previa.