Vasa praevia is a condition in which fetal blood vessels cross or run near the internal opening of the uterus. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.
Risk factors include low-lying placenta, in vitro fertilization.Vasa praevia occurs in about 0.6 per 1000 pregnancies. The term 'vasa previa' is derived from the Latin; 'vasa' means vessels and 'previa' comes from 'pre' meaning 'before' and 'via' ...
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