Trending Science: Womb with a view

The survival rate of babies’ born pre-term improves significantly after 23 weeks, going from nearly zero to 15 %. At 24 weeks that goes up to 55 % and by 25 weeks around 80 % survive. It is clear that every week in the womb during that vital time means the difference between life and death.

A recent breakthrough allowed lamb foetuses to grow and mature by providing them with a nutrient-rich blood supply and a protective sac of amniotic fluid in what researchers call a ‘biobag’. This is translucent, permitting researchers to watch how the foetus is developing.

Each artificial womb contains a mixture of warm water and salts, which is inhaled and swallowed by the lamb as would normally happen. A special machine, connected to its umbilical chord, supplies the lamb with oxygen and nutrients. Its heart then pumps the depleted blood back to the machine to be replenished before it returns to the lamb’s body.

Speaking to the BBC, Dr Emily Partridge explained the research is trying to aid the chances of a 23 to 24 week baby, ‘(…) who is faced with the a challenge of adapting to life outside of the uterus on dry land, breathing air when they are not supposed to be there yet.’

The premature lambs involved in the study were at a developmental stage equivalent to that of a 23-week-old human and all appeared to develop normally in their bags. After 28 days the lambs were released to ascertain if they could breath air freely. On birth, their coats were wooly and throughout the experiment they appeared comfortable. The first group was then killed in order for researchers to examine their brain and organ development while some of those involved in later experiments were bottle-fed by the team.

Adapting the technology to the needs of premature babies

Dr Marcus Davey, a researcher involved in the experiment explained that they were envisaging a system that would look very much like a traditional incubator. ‘It will have a lid and inside that warmed environment would be the baby inside the biobag,’ he said.

Challenges facing the transference of the technology to the care of premature babies include the risk of infection and defining the right combination of nutrients. A perception problem could also be a barrier as the parents involved will need to be taken on board.

Prof Colin Duncan, professor of reproductive medicine and science at the University of Edinburgh, told the BBC: ‘This study is a very important step forward. There are still huge challenges to refine the technique, to make good results more consistent and eventually to compare outcomes with current neonatal intensive care strategies.

‘This will require a lot of additional pre-clinical research and development and this treatment will not enter the clinic any time soon.’