Universe Today
Space travel has taught us valuable lessons for living and working in outer space, specifically regarding how microgravity (often mistakenly called zero-gravity) impacts the human body during short- and long-term spaceflight. This includes decreased muscle and bone mass, fluid shifts, reduced heart rate, psychological health, compromised immune system, and radiation exposure. But with agencies like NASA aspiring to build a lunar base and establish a long-term presence on the Moon, and eventually Mars, how could space travel impact potentially having babies in space?
Now, a team of researchers from Australia dares to address growing concern, as they performed a series of laboratory experiments designed to simulate microgravity and how it impacts sperm fertilization using sperm samples from a human, pig, and mouse over a four-hour period. Their findings were recently published in Communications Biology, with the researchers focusing on how microgravity impacts how the sperm both swims down a channel and finds an egg. Sperm typically uses a myriad of tactics to locate and fertilize an egg, including swimming against the flow of fluid and following chemical signals. The motivation for this study stems from a knowledge gap in how space travel impacts reproduction, and the researchers note filling this knowledge gap will be crucial for long-term space missions and planetary settlements.
In the end, the researchers found that human sperm’s navigation was altered but its ability to swim was not, with the former being addressed through progesterone, which acts as a chemical cue to guide the sperm toward the egg. For the mice, the researchers found a 30 percent decrease in successfully fertilized eggs and the researchers also found a decrease in successful fertilization for pig sperm, as well.
The study notes, “With the recent advancements in space travel and international interest in deep space exploration, Mars settlement and Moon mining, it is critical to investigate the effect of microgravity on early fertilization events not only for creating viable food sources, but also maintaining human space settlements, without the need to continually re-populate from Earth.”
This study builds on an expansive body of research dating back to the 1980s that has explored how microgravity impacts sperm. These include Soviet space missions in the 1980s that explored animal mating and pregnancy in space and experiments aboard the Internation Space Station that explored human sperm function. However, this most recent study could be the first to identify the navigational mechanisms that are influenced under microgravity, along with how to fix it.
This study comes as NASA recently announced plans to build a Moon base near the lunar south pole through the Artemis Program, with NASA Administrator Jared Isaacman having the goal of establishing a permanent human presence on the Moon. Through this, NASA plans to use its Moon to Mars Architecture program to develop and test new technologies on the Moon that can be used for future crewed missions to Mars.
Most recently, Artemis II successfully sent four humans around the Moon for the first time since 1972, and Artemis III is scheduled for 2027 to test docking maneuvers, with Artemis IV and V scheduled for 2028 and both slated to be landing missions to the lunar south pole. Therefore, studies like this highlight the importance of understanding how long-term space habitation could impact human reproduction, especially if humanity wants to live permanently among the stars.
“As we progress toward becoming a spacefaring or multi-planetary species, understanding how microgravity affects the earliest stages of reproduction is critical,” said Associate Professor John Culton, who is the Director of the Andy Thomas Centre for Space Resources at Adelaide University.
What new insight into space travel and human fertility will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
