Fetal surgery

Fetal surgery is a highly specialized field in fetal therapy for performing intrauterine manipulations, without which, in certain conditions, the unborn baby would not have a chance to live.

специалист по фетална медицина на болница "Надежда" се подготвя за вътреутробна операция

Treatment of fetal anaemia

The causes of fetal anaemia are numerous and of various nature.


The most common cause is incompatibility by rhesus factor blood group. This happens in case of a mother with a negative rhesus factor and a foetus with a positive rhesus factor, inherited from a rhesus-positive father. Anti-Rhesus antibodies are most often directed against the D antigen of erythrocytes but may also be against the C or E antigen. All these antibodies may, passing from the mother’s blood through the placenta, reach the foetus’s blood and lead to the destruction of its erythrocytes and cause severe life-threatening anaemia. The amount of antibodies is not equivalent to the degree of anaemia. Severe anaemia can also be seen with a relatively low antibody titer.


It is important to know that already in the first pregnancy of a mother with a negative rhesus factor, antibody formation and severe fetal anaemia may occur.
For this reason, prophylactic administration of anti-D immunoglobulin is recommended at 28 gestational week in the case of a previously proven absence of antibodies in the mother to prevent their occurrence, because the risk of foetal blood passing into the maternal circulation and inducing an immune response in the maternal organism at this term of pregnancy is the greatest.

Rarer causes of anaemia are:

Severe fetal anaemia leads to heart failure, as a result of which water (hydrops) begins to accumulate in the various body cavities of the foetus as well as in the skin. The condition worsens avalanche-like and if left untreated leads to intrauterine death of the foetus.

In cases of severe fetal anaemia after the 19-th gestational week, intrauterine haemotransfusion may be undertaken, in which the foetal anaemia is corrected by blood from an adult donor.


Intrauterine haemotransfusion is a treatment that takes place in an inpatient setting. Given the course of the condition is without complications, the hospital stay is three days.

Laser therapy for feto-fetal transfusion syndrome (FFTS)

30% of twins are derived from a single fertilized egg, i.e. they are monozygotic.

Most of the identical twins share a common placenta. For this reason, pregnancy with identical twins requires special care. Complications in them are much more common as compared to dizygotic twins. Identical twin babies have a higher incidence of growth retardation in one or both twins, as well as a higher rate of malformations.

Due to the fact that they share a common placenta and normally have vascular connections that pass from one part of the placenta to the other, 15% of identical twins develop a condition called feto-fetal transfusion syndrome (FFTS). This condition develops most commonly between the 16-th and 26-th gestational week.

In rare cases, it may occur earlier in gestation.

In FFTS, when the volume of blood exchanged between the twins becomes unequal (one twin gives more to the other), both babies become ill.

Due to lack of enough blood, the twin who gives to the other stops passing urine. On the one hand, this leads to a critical reduction in the baby’s amniotic fluid, and on the other, it can be the cause of stunting. The twin receiving blood has an excessively large blood volume and, by increased urine output, attempts to reduce it. In doing so he has (retains) an excessive amount of water and in most cases is much larger than the giving twin.

The increased amount of amniotic fluid may lead to contractions, shortening of the cervix and very often to loss of the pregnancy.

Alarming signs of this condition are a hard and tense pregnant belly, its too rapid growth (in a matter of days) and contractions.

Important! The monitoring of a pregnancy with identical twins should be carried out by a specialist qualified to do so, who has the necessary equipment enabling him to perform Doppler examinations of all foetal vessels very early in the course of pregnancy.

The first visit to such a specialist is recommended at 12-th gestational week follow-up visits should be appointed at every 2 weeks after the 16-th gestational week.

Nadezhda Hospital offers the option of laser coagulation therapy of the vascular connections between the two twins. Without therapy, the condition results in a high mortality rate and pregnancy loss or foetal harm.

In the later gestational period, monitoring of the pregnancy should be continued during certain periods, depending on its course.

In 2015, Nadezhda Hospital invested in state-of-the-art equipment, which allowed the treatment of feto-fetal transfusion syndrome to be launched.

The procedure is performed by Christina Chacheva, M.D., Head of the Prenatal Diagnostics and Therapy Department with many years of experience at the largest German prenatal center in Bonn.

The operation is bloodless and involves a few days stay in the hospital. It is performed with regional anaesthesia (epidural anaesthesia). A 5-millimetre incision is made in the mother’s abdominal wall, through which fine instruments are used to penetrate with a camera into the amniotic bladder of the recipient (the baby receiving blood from the other twin) and to locate the vessels on the surface of the placenta that connect the two foetuses. These vessels are closed using laser energy.

Depending on the location of the placenta and the difficulty of access, the procedure lasts between half and one hour and is not painful for either the mother or the babies.

After the operation, the condition of the babies needs to be monitored extremely carefully by specialists who are appropriately qualified in that regard.

See also

First trimester combined screening
Invasive techniques for prenatal diagnosis
Fetal anomaly scan
Non-invasive prenatal diagnosis (NIPD)