“We hope [the experiment] will provide scientific support for future human reproductive activities in space,” he was quoted as saying by People’s Daily, the Communist Party’s mouthpiece.

China’s first space station will soon begin construction with completion scheduled around 2020. The space station will significantly increase the span of Chinese astronauts’ stay in space from the present couple of weeks to several months.

“I will be thrilled to see a baby born in space, Chinese or not,” said Helen Yu Min, a resident in Beijing who was planning to have a second child.

China, which has the largest population in the world, is expected to have a new baby boom after the government terminated the one-child policy earlier this year.

“A space baby will put a smile on the face of every one on Earth,” Yu said.

But professor Tan Xin, a space biologist who studied the effect of microgravity on mammalian reproduction at the Beijing Institute of Technology, said having a baby in space was not as romantic as it sounded.

“It is a controversial issue complicated by many scientific, technical and ethical challenges,” he said.

First of all, no one had tried to make babies in space, he said.

The closest attempt was an experiment by former Soviet Union in 1979, which took a chamber of five female and two male mice for a two-day mating party in orbit.

The result turned out to be a complete failure. Scientists found no pregnancy or any sign of sexual intercourse. They suspected the animals lost interest in sex when exposed to the weightless environment.

But sex was not the biggest obstacle, according to Tan.

After conducting many experiments in simulated microgravity environment on ground, his team found that animals’ reproductive organs would degenerate or suffer damage, which implied that natural conception in space might be impossible without special intervention or medication.

“The bigger the animal, the more serious the problem,” he said.

Their findings were similar to the experiments by US space agency Nasa on ISS, which found that long-term space flight could reduce sperm count and hurt ovary cells that produced eggs in rodents.

“We are still left very much in the dark about the mechanism of reproduction in space. It is difficult to comment on the new findings without seeing a paper,” said professor Tang Fuchou, a developmental biologist with Peking University.

Duan told Xinhua news agency that their experiment was unlikely to produce “alien mice” as the blastocysts would have died as they returned to the earth.

Though photos showed that the mice’s blastocysts looked almost identical to those developed on the ground, the team would conduct further analysis on the returned samples to determine whether they had experienced any mutations in the microgravity environment, Duan said.

There was a chance that a space baby could be more “perfect” than those born on earth because the embryo could develop freely in all directions in the microgravity environment, according to Tan. But whether the embryo could eventually develop into a full infant are still uncertain.

“These experiments may provide hints to solve some reproductive health issues on Earth. Duan’s team made an important first step,” he said.

Having a baby in space would be an inevitable topic as humans extended the range of space exploration to other planets such as Mars, Tan said.

“When it will happen depends very much on the determination by the governments of space-faring nations,” he said.

The Shijian 10 mission was launched earlier this month, carrying various research instruments to conduct 20 scientific experiments during its 12-day flight, including the world’s first coal combustion experiment in space.

The returned capsule touched down in Inner Mongolia at 4.30pm on Monday.