Please send any questions for future editions. Flying can expose reproductive cells and the unborn to ionizing radiation. Ionizing radiation can cause genetic defects. In most cases, the levels of radiation on board an aircraft translate to a low level of risk to the unborn child. With an increase in solar activity comes an increase in solar flares.
Astronauts are at much greater risk than crew of commercial aircraft.
However some aircraft are exposed to increased levels of radiation during solar storms. Earth's atmosphere and magnetosphere allow adequate protection for us on the ground, but astronauts in space are subject to potentially lethal dosages of radiation. The penetration of high-energy particles into living cells, measured as radiation dose, leads to chromosome damage and, potentially, cancer. Large doses can be fatal immediately. In October 1989, the Sun produced enough energetic particles that an astronaut on the Moon, wearing only a space suit and caught out in the brunt of the storm, would probably have died.