The umbilical cord is one to two centimetres thick and 50 to 60 centimetres long. It connects the unborn child to the mother's body via the placenta and supplies it with blood and nutrients. The fetal umbilical cord vessels do not normally run in the membranes, but directly from the placenta to the child.
However, if the fetal umbilical cord vessels are located in the membranes, this is referred to as insertio velamentosa. If they are also located in the membranes in front of the inner cervix, this is a vasa praevia.
If the membranes rupture, these blood vessels can burst. This may cause the fetus to lose a critical amount of blood. If severe bleeding occurs, this can mean death for the fetus.
On the one hand, a slow heart rate can be observed in a vasa praevia. Secondly, affected women experience vaginal bleeding when the membranes rupture.
This bleeding is often painless and usually begins shortly after labor has started.
Experts and contact persons for vasa praevia are gynecologists, i.e. specialists in gynecology, and in particular obstetrics specialists.
Depending on the status of the pregnancy, you should consult your gynecologist or be admitted directly to hospital.
In a vasa praevia, the umbilical cord runs in front of the inner cervix © bilderzwerg | AdobeStock
Regular ultrasound examinations are part of medical pregnancy care. They should also be carried out in early pregnancy. Various abnormalities of the placenta can be detected using ultrasound.
To confirm the diagnosis of vasa praevia, a so-called transvaginal ultrasound is performed. To do this, the doctor inserts an ultrasound device into the woman's vagina. This allows him to check whether there are blood vessels near or above the opening of the cervix.
A particularly reliable diagnosis can be made using color Doppler ultrasound. This allows the blood flow within the vessels and the insertion on the membranes or placenta to be detected.
If a vasa praevia is detected before the onset of labor, various treatment options are available. The treatment depends, among other things, on how far the pregnancy has already progressed.
In any case, the expectant mother should be closely monitored by her gynaecologist. During the 30th to 32nd week of pregnancy, admission to hospital may also be advisable. This enables permanent monitoring of the unborn child.
In addition, the doctor can administer certain medications that stimulate the growth of the unborn child's lungs. These drugs are known as corticosteroids.
As a rule, patients with vasa praevia are delivered by caesarean section between 34 and 37 weeks of pregnancy. Such a caesarean section may have to be performed in an emergency. Such an emergency exists, for example, if
- the woman has heavy vaginal bleeding,
- the amniotic sac has broken,
- there is danger to the woman or the unborn child or
- a vasa praevia is only detected after labor has already begun.
Under certain circumstances, a vaginal birth is also possible. The prerequisite is that the fetal blood vessels are more than 2 cm away from the inner cervix (insertio velamentosa).
Early detection is an important prerequisite for planning the safest possible birth. Experienced doctors can use ultrasound to detect abnormalities in the umbilical cord early on in the pregnancy.
A vasa praevia can lead to very heavy bleeding in the unborn child. This usually occurs shortly before labor begins.
Such a complication can often already be suspected during early pregnancy. If vasa praevia is suspected, the doctor will carry out an ultrasound examination of the vagina.
Once vasa praevia has been diagnosed, close monitoring by the gynecologist is necessary. If problems become apparent, a caesarean section is necessary. Symptom-free patients are usually delivered by caesarean section between 34 and 37 weeks of pregnancy.