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s article (p. 163) on the graphic presentation of the progress of labour, I wondered if any of your readers would be interested in the simple tabular guide to when to start worrying about the duration of labour that I use in teaching the pupil midwives here. It is based on the times to send for medical aid in the second stage that every pupil midwife knows and works in multiples of two and four.
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Evans et al. (1972) studied this question.
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