You searched for: “contraindications
contraindication (s) (noun), contraindications (pl)
A condition which makes a particular treatment or procedure harmful: For some babies, aspirin is absolutely a contraindication because of the danger that aspirin will cause Reye syndrome which is a sudden, or sometimes fatal, disease of the brain (encephalopathy) and with degeneration of the liver.

Sometimes X-rays in pregnancy are relatively contraindicated, because of concern for the developing fetus; unless the X-rays are absolutely necessary.