During the pregnancy, a baby can become so anaemic that it is in danger of dying in utero. In the past, this was usually the result of Rhesus blood group incompatibility. With Rhesus incompatibility, the mother’s immune system develops antibodies which cause the baby’s red blood cells to break down. Nowadays, the most cases of foetal anaemia we see are the result of an infection with Parvovirus B19, a virus which causes “fifth disease”, an otherwise mild childhood disease which causes a “slapped-cheek” appearance.
Whichever the cause may be, if the baby becomes very anaemic in the uterus, it can cope to some extent, but runs the risk of developing cardiac failure (becomes “hydropic”) and dying. If the baby appears to be anaemic on Doppler ultrasound, everything will be organized for an intrauterine blood transfusion. The blood bank specially prepares O negative blood for the transfusion.
You will receive antibiotics to prevent an infection and medication to make you relax during the procedure, which can take up to an hour. In the ultrasound rooms or in the hospital ward, a thin needle is placed through your abdominal wall into the umbilical cord of the baby, and a blood sample is taken to check whether the baby is, in fact, anaemic. Part of the blood sample can also be sent for analysis of the baby’s chromosomes. If the baby is anaemic, we calculate how much blood the baby needs, and it is administered through the same needle. We usually give the baby medication which causes it to lie still during the procedure. This takes a few hours to wear off. If the pregnancy is early (before 20 weeks) it is difficult to give the transfusion through the umbilical cord, but it can also be given into the baby’s body cavity.
After the transfusion, it takes some hours before you feel the baby move again. If the baby is viable, i.e. after 26 weeks, we will also monitor the baby’s heart beat in the maternity ward for a few hours. Once the baby is vaible, preparations will also be made to make an urgent cesarean delivery possible if something goes wrong during the transfusion.
If the baby is not hydropic, there is a better than 90% chance of survival. If it is hydropic, the chances are much worse, because it can be so ill that it cannot tolerate the transfusion.
If the baby is anaemic because of a viral infection, it is usually only necessary to do one transfusion; sometimes a second, and the pregnancy can carry to term. If it is anaemic because of blood group antibodies, it is usually necessary to repeat the transfusion every two to three weeks, and the baby would be delivered a few weeks earlier.
After the intrauterine transfusion, other complications can occur, similar to those after a diagnostic cordocentesis. An amniotic fluid leak can develop, which happens in about 2% of people. If it does happen, you would notice a small amount of fluid leaking out vaginally. Usually, the amniotic fluid leak resolves if you stay in bed for a week. Labour can start prematurely. Symptoms of this are cramping abdominal pains, worse than menstruation pains, possibly combined with vaginal bleeding. An infection can develop in the womb. Symptoms of this are fever, cold shakes, a constant pain over the womb, and sometimes an offensive vaginal discharge. The baby’s condition could deteriorate unexpectedly, with reduced movements. If you notice any of these symptoms, please contact us or your gynaecologist immediately.
If you are HIV positive, there is an increased chance that HIV can be passed on to your baby if you have an intrauterine transfusion. If the viral load is low, the risk of transmitting HIV is low as well, and the risk of transmitting HIV would need to be weighed up against the risk of the baby dying if no transfusion is done.