Can a human get pregnant in space? New study highlights major challenges

A new study published in Science journal has found that human reproduction in space could be difficult because microgravity and cosmic radiation may affect fertility. Scientists discovered that sperm struggle to move in zero gravity, which could reduce the chances of pregnancy.

The research titled, ‘Human sperm navigation is impaired in microgravity conditions’, was conducted in recent years using simulated microgravity experiments and published in March 2026 in the journal. The study was carried out by an international team of researchers studying reproductive biology and space conditions.

Researchers tested human sperm in a microgravity simulation designed to act like a female reproduction tract. They found that sperm lost their sense of direction in zero gravity, reducing fertilisation rates by up to 30%. This makes it harder for sperm to reach the egg.

Humans have lived on the International Space Station for more than 20 years, showing that life in space is possible. However, astronauts face challenges such as floating conditions, special hygiene systems, and daily exercise to prevent bone and muscle loss. For future settlements on the Moon or Mars, reproduction will be necessary for long-term survival.

The study also showed that space radiation can damage DNA, increase cancer risk, and affect reproductive cells. Microgravity may also change hormone levels, which can reduce sperm and egg quality.

The senior author of the study said understanding reproduction in space is important as missions to the Moon and Mars become more realistic. Scientists also found that adding the hormone progesterone helped sperm move in the right direction, acting like a chemical signal from the egg.

Although progesterone improved sperm movement, researchers said it is not yet a simple solution. More studies are needed to understand whether humans can safely reproduce in space in the future.