Vasa Previa - An Avoidable Tragedy

Pregnancy. The months and weeks leading up to the birth of a child are some of a woman's most exciting times, filled with the anticipation, hope, and joy of giving birth to a new life. When all goes well during the pregnancy, labor, and delivery, a beautiful healthy baby comes into the world. But what happens when a condition goes undetected or is misdiagnosed? If the condition is vasa previa, it means that 50-95% of the babies will die. Even in today's modern medical world of advanced technology and well-trained clinicians, oversights occur. This is especially true when it is a condition like vasa previa which is not part of the normal prenatal screening.

What is it? Vasa previa, reported in 1 of every 2,500 pregnancies, is a condition in which exposed fetal blood vessel(s) normally supported in the placenta or umbilical cord instead run through the amniotic membranes and cross the entrance to the birth canal, beneath the baby. The condition has a high fetal mortality rate (50-95%) due to rapid fetal hemorrhage resulting from the vessels tearing when the membranes rupture, or if the vessels become pinched off as they are compressed between the baby and the walls of the birth canal.

How does this occur? Blood vessels feeding the baby normally travel from the placenta through the umbilical cord and into the baby's bellybutton. With velamentous insertion of the cord, or certain other placental abnormalities such as bi-lobed placenta, parts of these fetal blood vessels run through the membranes instead of being supported in the placenta or covered by the Wharton’s jelly surrounding the umbilical cord. Velamentous vessels can develop as a low-lying placenta moves up in the uterus. This in itself is not uncommon, occurring once or twice in every 100 pregnancies. It is not necessarily life threatening or symptomatic and many babies with velamentous vessels are born without any problems at all. Pregnancies with exposed (velamentous) vessels located between the baby and the cervical opening (vasa previa) are in serious trouble, however. Velamentous vessels located between the baby and its way out will tear or break causing a large bleed which will compromise the baby immediately. Birth is disastrous for babies with vasa previa. These children share the womb with a time bomb.

So what can be done to save vasa previa babies? Infant death from vasa previa is preventable. Due to lack of awareness about this heartbreaking condition the infant death rate can be as high as 95%. However, 100% of prenatally diagnosed and properly managed vasa previa babies survive. It doesn't take high level ultrasound to diagnose, only awareness. Research shows that successful management consists of pelvic rest, hospitalization at 30-32 weeks, and C-section delivery by about 35 weeks.

Transvaginal ultrasound (an ultrasound view of the cervix) in combination with color Doppler (which shows blood flowing through veins) is the most effective tool in the diagnosis of vasa previa during pregnancy and should be utilized in patients at risk, specifically those with velamentous cord insertion, succenturiate-lobed and/or low-lying placentas (even if it corrects itself!), pregnancies resulting from in-vitro fertilization, multiple gestation (twins), painless bleeding, and women with a maternal history of uterine surgery (including C-section and/or D&C). Transvaginal ultrasound gives an excellent and direct view of the cervix. Turning on the color Doppler makes it possible to see vessels that may be crossing the cervical opening.

When vasa previa is detected prior to labor, the baby has a much greater chance of surviving. IVPF records show that 100% of prenatally diagnosed and appropriately managed babies survive vasa previa in the absence of other complications. Despite improvements in medical technology, poor awareness of the condition often leads to that fatal fetal vessel rupture. When vasa previa is found, hospitalization at 30-32 weeks and elective delivery by cesarean before labor begins can save the baby's life. Aggressive resuscitation and immediate blood transfusions for the neonate is necessary when a vasa previa rupture has occurred. Delivery and transfusion cannot occur quickly enough if the rupture occurs and the mother is not already in hospital. Without prenatal diagnosis, hospitalization, and early C-section, a vasa previa baby is almost sure to die. It only takes a moment to diagnose life...

Courtesy of the International Vasa Previa Foundation