- Conception in space is difficult due to microgravity, but pregnancy may proceed normally once implanted
- Childbirth and newborn care in zero gravity would be complex due to floating fluids and lack of gravity
- Cosmic rays in space pose serious risks to embryos and foetuses, causing cellular damage and mutations
As space agencies plan manned missions to Mars, concerns about human reproduction in space have arisen. Notably, a round-trip to Mars could span the entire duration of a pregnancy, raising questions about the feasibility of conception and safe childbirth in space. According to Science Alert, conception in space might be physically challenging due to microgravity, but once an embryo implants, the pregnancy could likely proceed normally. However, childbirth and newborn care would be significantly more complicated in zero-gravity environments.
In his research, scientist Arun V. Holden explained that without gravity, fluids and people float, making delivery and infant care messy and complex. Tasks like positioning and feeding, which are effortless on Earth thanks to gravity, would become much more difficult in space.
Interestingly, a developing fetus already experiences a microgravity-like environment in the womb, floating in amniotic fluid that's neutrally buoyant. This environment cushions and suspends the fetus, somewhat similar to the weightlessness astronauts experience in space. Astronauts often train for spacewalks in water tanks that simulate microgravity, mirroring the weightless environment of the womb. However, gravity is not the only problem.
Beyond Earth's protective atmosphere, cosmic rays pose a significant threat. These high-energy particles are essentially bare atomic nuclei, stripped of their electrons, racing through space at nearly the speed of light. Composed of protons and neutrons, they're incredibly dense and can cause severe cellular damage when they collide with the human body. This risk is particularly concerning for deep space missions, where exposure to cosmic rays could have lasting effects on both mother and fetus.
On Earth, we're shielded from most cosmic radiation by our atmosphere and magnetic field, which provides tens of thousands to millions of miles of protection depending on the time of day. However, in space, this protection vanishes.
When cosmic rays interact with the body, they can cause highly localised damage, destroying individual cells or cellular components while leaving surrounding tissue intact. If a ray hits DNA, it can lead to mutations that increase cancer risk. Even when cells survive, radiation can trigger an inflammatory response, causing the immune system to overreact and release chemicals that damage healthy tissue and disrupt organ function.
During the initial weeks of pregnancy, embryonic cells undergo rapid division, migration, and tissue formation, making this a critical period for development. The first month post-fertilisation is particularly vulnerable, and a single high-energy cosmic ray could potentially be dangerous to the embryo. Given the embryo's small size, a direct hit is, however, unlikely. If such an event were to occur, it would likely result in a miscarriage that might go unnoticed.
As pregnancy progresses, the risks associated with cosmic radiation shift. Once the placental circulation is fully formed by the end of the first trimester, the fetus and uterus grow rapidly, presenting a larger target for cosmic rays. A hit to the uterine muscle could trigger contractions and potentially cause premature labour, which carries a higher risk of complications, especially in space where medical resources are limited.
Further, a baby born in space would face unique developmental challenges due to microgravity. The absence of gravity could interfere with the development of postural reflexes and coordination, affecting the child's ability to learn essential motor skills like lifting its head, sitting up, crawling, and walking.
The risks associated with cosmic radiation persist even after birth, as a baby's brain continues to develop and grow. Prolonged exposure to cosmic rays could lead to permanent damage, impacting cognition, memory, behaviour, and long-term health. While it's theoretically possible for a baby to be born in space, there are many challenges to be overcome.
