It's time to think about human reproduction in space, scientists urge

Two adult astronauts and one child-sized astronaut with dark helmets stand on a red surface with domed buildings nearby

What will the first families in space look like? (Image credit: Denis-Art/Getty Images)

As humanity moves from brief space missions toward longer stays — driven by commercial ambitions for moon bases and eventual Martian settlements — scientists are beginning to confront how the conditions of space may affect human reproduction.

A new study argues that the absence of clear evidence and shared standards around reproductive health beyond Earth has propelled the issue from an abstract possibility into what the authors describe as "urgently practical."

Rather than advocating for conception in space, the study's nine authors — experts in reproductive medicine, aerospace health and bioethics — say their goal is to identify foreseeable risks and highlight gaps in research and governance that could become problematic as human activity in space expands, before technological and commercial momentum outpaces ethical oversight.

"As human presence in space expands, reproductive health can no longer remain a policy blind spot," study co-author Fathi Karouia, a senior research scientist at NASA, said in a statement.

"International collaboration is urgently needed to close critical knowledge gaps and establish ethical guidelines that protect both professional and private astronauts — and ultimately safeguard humanity as we move toward a sustained presence beyond Earth."

IVF in space?

More than half a century ago, two breakthroughs reshaped ideas about what was biologically and physically possible, the study notes, in reference to the first human landing on the moon and the first successful fertilization of a human egg outside the body through in vitro fertilisation, or IVF.

"Now, more than half a century later, we argue in this report that these once-separate revolutions are colliding in a practical and underexplored reality," Giles Palmer, a senior clinical embryologist at the International IVF Initiative who led the new study, said in the statement.

"IVF technologies in space are no longer purely speculative," Palmer added. "It is a foreseeable extension of technologies that already exist."

Over that same period, spaceflight has evolved from an elite, male-dominated endeavour tied to national prestige into a rapidly expanding frontier shaped by commercial ventures and international collaboration. Alongside career astronauts, private citizens are now flying on commercial missions, while space agencies and companies are planning sustained human presence beyond low Earth orbit.

Meanwhile, assisted reproductive technologies have become more advanced, automated and accessible, the researchers say, yet fundamental biological questions about reproduction remain unanswered, particularly for long-duration missions.

"As human activity shifts from short missions to sustained presence beyond Earth, reproduction moves from abstract possibility to practical concern," Palmer said in the statement.

What scientists do know from limited laboratory experiments and astronaut data is that space presents a demanding environment for human biology. Exposure to cosmic radiation, altered gravity, disrupted circadian rhythms, psychological stress and prolonged isolation all pose potential risks to reproductive function in both women and men.

Radiation is among the most serious concerns. Unlike on Earth, where the atmosphere and magnetic field provide substantial protection, astronauts are exposed to galactic cosmic rays and solar radiation.

Reproductive tissues are particularly sensitive to DNA damage, the study notes, and the effects of cumulative radiation exposure on male fertility during extended missions represent what the authors describe as a "critical knowledge gap."

There are currently no widely accepted, industry-wide standards for managing reproductive health risks in space, the study notes. The researchers highlight unresolved questions around preventing inadvertent early pregnancy during missions, understanding the fertility impacts of microgravity and radiation, and setting ethical boundaries for any future reproduction-related research beyond Earth.

"If reproduction is ever to occur beyond Earth," the study notes, "it must do so with a clear commitment to safety, transparency and ethical integrity."

This research is described in a paper published Feb. 3 in the journal Reproductive Biomedicine Online.

Sharmila Kuthunur is an independent space journalist based in Bengaluru, India. Her work has also appeared in Scientific American, Science, Astronomy and Live Science, among other publications. She holds a master's degree in journalism from Northeastern University in Boston.

You must confirm your public display name before commenting

Please logout and then login again, you will then be prompted to enter your display name.