Umbilical Cord Insertion to the Lower Uterine Segment Is a Risk Factor for Vasa Previa

Abstract

The perinatal mortality rate of vasa previa is high if it is not prenatally diagnosed. Systematic strategies for vasa previa screening have been recommended. In this paper, three cases of vasa previa diagnosed prenatally, with umbilical cord inserted to the lower segment of the uterus, are presented. It should be considered that umbilical cord insertion to the lower uterine segment is a high risk for vasa previa. Ultrasound screening for cord insertion will make it possible to do efficient and certain detection of vasa previa.

Prenatal diagnosis and management of vasa previa: A 6‐year review

“…As shown in Table 2, all of the present cases had one or more known risk factors; in particular, all cases had cord insertion to the lower uterine segment. The relationship between cord insertion to the lower uterine segment and vasa previa was first reported by Hasegawa et al 9 . IVF is also reported as a risk factor for vasa previa.…”

“…Data extracted from the medical records included the reason for referral, gestational age at diagnosis of vasa previa, gestational age at delivery, birth weight, Apgar scores, pH of the umbilical artery, and known risk factors for vasa previa, such as second trimester low‐lying placenta, placenta with accessory lobes, multiple pregnancy, pregnancy resulting from in vitro fertilization (IVF), 8 and cord insertion to the lower uterine segment 9 …”

Sonoembryological evaluations of the development of placenta previa and velamentous cord insertion

“…Several studies have reported a higher incidence of velamentous cord insertion in assisted reproductive technology pregnancies, as the exact chronological succession of biological events required for proper blastocyst implantation is disturbed in more than one phase in cases of assisted reproduction . Various risk factors associated with vasa previa have also been reported in previous studies, including the ultrasound diagnosis of a low‐lying placenta or placenta previa at early gestation, a bi‐lobed or succenturiate placenta, multiple gestation and cord insertion into the lower uterine segment . In view of our results, we believe that causative mechanisms underlying these risk factors can be explained by the effects of abnormal polarity during blastocyst implantation and atrophic changes in the placenta in the lower uterine segment as a result of a poor blood supply (Fig.…”

Prediction of risk for vasa previa at 9–13 weeks' gestation

“…Various risk factors for vasa previa have been reported in previous studies, including the ultrasound diagnosis of low‐lying placenta or placenta previa at an earlier gestation, 2,4,8,9 a bi‐lobed or succenturiate placenta, 2,4,8,9 multiple gestations, 9 suspicion of aberrant vessels, 9,10 cord insertion into the lower uterine segment, 11 and pregnancy by in vitro fertilization 6,12 . Ioannou and Wayne 13 recently investigated obstetricians' views on the feasibility of a screening policy and their awareness of risk factors associated with vasa previa in England and Wales.…”