Your description of the safe period for abdominal radiology (6 December, p 543) is unfortunately imprecise, ambiguous, and could be misleading; it is not clear whether the beginning or the end of menstruation is intended. The circular from the Royal College of Radiologists admits of no ambiguity. It states that the safe period is "within the 10 days following the first day of the menstrual cycle" (my italics). Future periods are not mentioned.
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