To explore the risk factors and the value of ultrasound in prenatal diagnosis of vasa previa.

The ultrasound data of vasa previa pregnant patients, who were admitted to Guangdong Province Maternal and Child Health Hospital from January 2012 to June 2014, were retrospectively analyzed. The pregnancy outcomes were followed-up.

Eighteen vasa previa patients were antenatal diagnosed by ultrasound. One presentation of umbilical cord patient was misdiagnosed as vasa previa, and 1 case missed diagnosis. In the 18 vasa previa patients, 16 cases (88.9%, 16/18) were singleton pregnancy and 2 cases (11.1%, 2/18) were triplet pregnancy; 9 cases (50.0%, 9/18) were low-lying placenta, 8 cases (44.4%, 8/18) were velamentous placenta, 2 cases (11.1%, 2/18) were accessory placenta, 2 cases (11.1%, 2/18) were battledore placenta; and 3 cases (16.8%, 3/18) were single umbilical artery. There were totally 18 fetuses/newborns, 9 cases (50.0%, 9/18) were preterm birth, 8 cases (44.4%, 8/18) were full-term birth, and 1 case (5.6%, 1/18) underwent induced labor because of fetal malformation. For the missed diagnosis case, the patient occurred massive hemorrhage during vaginal delivery at full-term and the fetus died.

Placental abnormality is the risk factor of vasa previa. Emphasizing the prenatal ultrasound examination, diagnosing and managing timely, could avoid the occurrence of adverse pregnancy outcomes effectively for the vasa previa patients.