BBC Knowledge AUGUST 2017

Talk about a womb with a view... researchers at the

Children’s Hospital of Philadelphia in the USA have created

a plastic bag-like artificial womb and successfully used it

to incubate premature baby lambs for up to 28 days.

That’s a huge improvement on the maximum 60 hours

achieved in previous attempts to develop artificial wombs.

Extreme prematurity (where a baby is born less than

26 weeks into a pregnancy) accounts for one-third

of infant deaths in humans. Currently, premature babies

are placed in incubators, and put on ventilators to help

them breathe. But this can lead to lung problems later in

life, and the development of other organs is often impaired.

In contrast, the ‘biobag’ system developed in Philadelphia

is designed to more closely mimic conditions inside

the mother’s womb. The infant’s lungs ‘breathe’ amniotic

fluid, just as in a real womb, and their hearts pump blood

through an artificial umbilical cord into an external

oxygenator. This oxygenator is a substitute for the mother’s

placenta in exchanging oxygen and carbon dioxide.

Nutrients are supplied via the umbilical cord, while the bag

protects the foetus from changes in temperature and light,

as well as keeping germs at bay.

“[Extremely premature] infants have an urgent need for

a bridge between the mother’s womb and the outside

world,” said research lead Dr Alan W Flake. “If we can

develop an extra-uterine system to support growth and

organ maturation for only a few weeks, we can dramatically

improve outcomes for extremely premature babies.”

PREMATURE LAMBS LIVE IN

‘PLASTIC BAG’ WOMBS

PHOTOS: CHILDRENS HOSPITAL OF PHILADELPHIA, SALK INSTITUTE

ILLUSTRATION: DANIEL BRIGHT

The tiny lambs

appeared to develop

normally inside

the artificial wombs

BIOLOGY

Discoveries

science

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