Mia Africano, now 15 months, is in perfect health thanks to her pre-birth procedure.

Mia Africano, now 15 months, is in perfect health thanks to her pre-birth procedure. Photo: Jason South

Mia Africano was still in the womb when a common virus threatened to stop her bone marrow producing red blood cells. Doctors warned her parents that if they did not act, she might not survive.

The warning sign was a red rash on elder sister Monique's cheek, which doctors diagnosed as the common childhood illness parvovirus, also known as slapped cheek disease.

The virus usually causes only mild illness for preschool-aged children but can be dangerous for unborn babies. In rare cases, it can cause severe anaemia that can cause their tiny hearts to fail.

A delicate procedure.

A delicate procedure.

Carmel Africano was 26 weeks pregnant when she was diagnosed with parvovirus, and intense monitoring over the next few weeks showed the velocity of blood through Mia's brain was speeding up. That meant the baby's blood was thinning and she was becoming anaemic.

At 33 weeks doctors advised a foetal blood transfusion, a delicate procedure performed by the Royal Women's Hospital only about a dozen times a year. In the operation, specialist doctors inject donor blood into the umbilical cord to top up a baby's red blood cells, allowing the child to receive oxygen from her mother's placenta.

While the procedure can be life-saving there are risks, including tearing the cord and causing internal bleeding for the baby. Doctors warn parents there is a 2 per cent risk of miscarriage, and a chance they might need to deliver the baby on the spot if something goes wrong.

Associate Professor Ricardo Palma-Dias said it was always a tense moment when a needle was put into a woman's pregnant belly, at first to extract a blood sample to confirm the baby's anaemia and its severity. A haematology technician then takes the sample to instantly work out the baby's haemoglobin levels - and therefore how anaemic it is - so doctors can determine how much blood to transfuse.

In MIa's case, it was Professor Palma-Dias standing by with the needle. He injected the blood into her umbilical cord in August 2011, using an ultrasound screen to guide him.

Just as it was tense for doctors, Mrs Africano said she felt nervous as Professor Palma-Dias injected blood into her belly. "I was awake. I couldn't even watch. I had a local [anaesthetic] on my belly and they gave Mia a needle as well to calm her down so she wouldn't move," she said.

The blood transfusion quickly showed signs of working, with an ultrasound performed just days later showing that Mia's haemoglobin levels had improved.

Besides parvovirus, another common reason for a transfusion is when a mother and unborn baby have the incompatible blood groups rhesus negative and rhesus positive. In such cases a mother's body assumes the baby's blood cells are alien and produces antibodies to destroy them, resulting in the baby becoming anaemic.

Multiple injections are required when the mother and baby have incompatible blood types, but in Mia's case just one transfusion was enough to top up her red blood cells while she recovered from parvovirus.

Professor Palma-Dias, who is head of the Royal Women's Hospital's foetal medicine unit, said such procedures could have a huge impact. "If you save a little life that has, who knows, 80 years … it's priceless," he said.

Mrs Africano gave birth to Mia at 37 weeks and said the now 15-month-old was in perfect health, adding, "She's pretty cheeky, she gets into everything … and she's always smiling."