It is a question that has perplexed scientists for decades: could humans ever have babies in space? Now, China has taken a significant step towards a definitive answer. The nation has become the first in the world to send 'human artificial embryos' into orbit.
Mission Details
The embryos arrived at China's Tiangong space station in the early hours of May 11, traveling aboard the Tianzhou-10 resupply mission. They were allowed to develop for five days, 280 miles (450 km) above Earth, before being frozen for later analysis. Once back on Earth, scientists will compare their development to those grown on the ground to determine if the harsh space environment causes problems for human reproduction.
This experiment is a crucial step towards China's ambition of establishing a permanent human presence beyond Earth's atmosphere. Leqian Yu, a researcher at the Chinese Academy of Sciences' Institute of Zoology leading the experiment, hopes it will 'address the risks and challenges humans may face during long-term space habitation.'
What Are Artificial Embryos?
Artificial embryos are collections of stem cells that resemble real human embryos in key aspects but cannot develop into a fetus. This allows researchers to investigate human development with fewer ethical concerns. Dr. Yu stated: 'The human artificial embryo is made of human stem cells as raw materials. This is not a real human embryo and does not have the ability to develop into an individual.'
The researchers sent two different types of artificial embryos to the space station, each representing a critical stage in human development:
- Peri-implantation model: Designed to mimic the moment an embryo attaches to the uterine wall.
- Peri-gastrulation model: Replicates the stage when a single layer of cells splits into layers that will form different tissues and organs.
Dr. Yu explained: 'This stage is a critical window in early human development, during which the building blocks for future organs begin to form, and the entire body axis — which determines the head and the tail — is established. Therefore, these models were brought to space to explore whether life, which has evolved under gravity for hundreds of millions of years, is affected by its sudden absence.'
Why Study Reproduction in Space?
Scientists want to see if the mechanisms dictating embryo development can function without gravity. Microgravity might lead to developmental defects, potentially making human reproduction in space impossible. Since these conditions are nearly impossible to recreate on Earth for extended periods, artificial embryos must be sent into space to find out.
Similar experiments involving zebrafish and mouse embryos were also sent aboard Tianzhou-10, alongside 6.3 tonnes of cargo including food, fuel, and space suits for the crew.
Dr. Yu added: 'By comparing embryo development in space with that on the ground, we can investigate how the space environment impacts critical events in human development.'
Challenges of Space Reproduction
For humanity to become a space-faring species, safe reproduction is essential. However, conditions beyond Earth may pose barriers. Previous studies have shown that microgravity interferes with reproduction, modifying the number of fetal cells within an embryo. Sperm can become 'disoriented' in microgravity, lowering conception chances. Additionally, cosmic radiation bombards spacecraft, potentially causing genetic damage and increasing risks of cancer or birth defects.
Nevertheless, research is progressing. Last year, Kyoto University researchers showed that mouse egg and sperm cells could survive in space and produce healthy offspring. Dutch biotech startup Spaceborn United has also launched a miniature lab for IVF into orbit.
Future Prospects
Some experts predict that children could be born on the moon within decades. Professor Bernard Foing, ambassador of the European Space Agency's 'Moon Village' scheme, suggested that by 2050, families could join lunar colonies as settlements grow. This experiment by China is a vital step toward understanding and overcoming the challenges of human reproduction in space.
