Pregnancy Diagnostics Glossary
100 terms total — 4 showing — Last updated 15 Sep 2026
PROM PROM
Premature rupture of membranes occurring before the onset of labor, requiring assessment of gestational age and infection risk.
vanishing twin syndrome
A phenomenon where one twin in a multiple pregnancy is reabsorbed early in gestation, leaving a singleton pregnancy.
Vasa previa
Condition where fetal blood vessels cross the cervical opening, creating risk of vessel rupture during delivery.
Velamentous cord insertion
Abnormal umbilical cord attachment where vessels insert into fetal membranes rather than directly into placental tissue.
Yolk sac
Small circular structure visible on early ultrasound within the gestational sac, important for early pregnancy assessmen...