Romping in space is a “real concern” for astronauts, a top university professor has warned.

It’s something we know little about — but it’s crucial if we ever want to colonize other planets like Mars.

During a recent Atlantic Live panel, Kris Lehnhardt, an assistant professor at George Washington University, said the topic needs to be addressed immediately.

He said: “It’s a real concern … something we really don’t know about is human reproduction in space.”

“If we actually want to go places and stay there, there’s a key component and that’s having babies,” he added.

It’s hard to imagine getting it on during a rocket mission, considering the lack of gravity.

And spacesuits aren’t the most appealing when it comes to foreplay.

But during the long mission to Mars (which Elon Musk hopes to make a reality by 2030), it’s likely to happen.

There are many things that humans need to prepare for before attempting long-duration space travel.

Combating the radioactive space rays beaming from the sun, keeping your health in good condition and maintaining your fitness are likely to be prime concerns for astronauts.

But sexual reproduction is probably the most important, according to Lehnhardt.

“If we want to become a spacefaring species and live in space permanently, this is a crucial issue we need to address that has not been fully studied yet,” he said.