Synthetic 3D-printed ovaries help infertile mice have pups

Fully functional 3D-printed ovaries have been successfully implanted in mice for the first time - enabling them to have healthy offspring.

A team led by researchers at Northwestern University, Illinois, removed ovaries from female mice and replaced them with bioprosthetic ones that were capable of ovulating. The mice became pregnant naturally and gave birth to pups that thrived with their mothers' nursing.

Previous experiments have restored fertility in female mice using egg follicle cells or ovarian tissue implants, but this is the first time a whole synthetic ovary has achieved the same outcome.

'Our hope is that one day this ovarian bioprosthesis is really the ovary of the future,' said Dr Teresa Woodruff, director of the Women’s Health Research Institute at Northwestern University's Feinberg School of Medicine, to The Guardian. So far the procedure has only been tested in animals, but scientists hope eventually to be able to restore fertility to women with infertility issues, or who have reduced fertility due to cancer treatment.

The key to the success of the bioprosthetic ovary in this study appears to be due to the geometry of the 3D scaffold the team used to build the organ. The scaffold structure consisted of layered lattices of gelatin made at a temperature that allowed the structure to be strong enough to survive surgery, but porous enough to interact with body tissues. Crucially, the architecture of the scaffold also seemed to help ovarian follicles - the hormone-producing cells around the immature egg cells - to survive.

'This is the first study that demonstrates that scaffold architecture makes a difference in follicle survival,' said Professor Ramille Shah of Northwestern University. 'We wouldn't be able to do that if we didn't use a 3-D printer platform.'

Within a week of being implanted into the mice, the bioprosthetic ovaries hooked up to the animals' blood supplies and began releasing eggs through pores in the gelatin structures. When the mice were allowed to mate, three of the seven female mice with bioprosthetic ovaries gave birth to healthy litters.

The team is now working on enlarging the scaffold to make it possible to test the treatment on larger animals, and eventually humans. The study was published in Nature Communications last week.