Which may be effects of fetal irradiation?

• A. Childhood and early adult cancers.
• B. Prenatal death.
• C. Cancers late in adult life.
• D. Growth retardation.

Answer: (B)

Exposure to ionizing radiation during pregnancy is especially risky because the fetus is highly radiosensitive, particularly during early development when cells are rapidly dividing. When the dose is high enough, the damage can be catastrophic for the developing fetus, leading to fetal death before birth. This outcome is a deterministic effect, meaning it has a threshold dose and becomes more likely as the dose increases, making fetal death a direct and well-established consequence of substantial fetal irradiation.

Other potential effects, like growth retardation or cancers that may appear later in childhood or adulthood, are possible but depend on lower doses or longer time frames and are not as certain or immediate as prenatal death. Cancers later in life are stochastic effects with variable risk, and growth retardation can occur but isn’t as definitively tied to the exposure as fetal death at high doses.