Changes in the cervical blood flow during labour

The cervical blood flow changes during labour in pregnant women (15 cases) have been studied by local injection of 133Xe into the cervix. The blood flow changes were compared with the external uterine pressure which was measured with a tocograph. During contractions the radioactivity decreased temporarily, but increased again between contractions. The overall decrease was greater in the control group (4 cases) than during spontaneous contractions. The conclusion is, that relative cervical blood circulation is rapidly changed during labour.

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