|Care in Normal Birth (WHO, 1996, 60 p.)|
|3. CARE DURING THE FIRST STAGE OF LABOUR|
Several studies show that, during the first stage of labour, the supine position affects the blood flow in the uterus. The heavy uterus can cause aortocaval compression and the reduced blood flow can compromise the condition of the fetus. The supine position is also found to reduce the intensity of the contractions (Flynn et al 1978, McManus and Calder 1978, Williams et al 1980, Chen et al 1987), and thus interferes with the progress of labour. Standing and lying on the side are associated with greater intensity and greater efficiency of the contractions (their ability to accomplish cervical dilatation).
Despite the continued prevalence of the supine position many options are open to women in labour. However, various constraints frequently limit those options, from the design of the delivery-suite bed to delivery protocols or the presence of routine intravenous lines or monitoring equipment. Where such constraints are kept to a minimum women can stand, walk, sit upright or on hands and knees, take a shower or a bath to relax or adopt each position alternately as they choose. Trials that have compared these positions to the supine have found that, on average, labour was experienced as less painful (there was less need for analgesia) and augmentation was used less frequently in the non-supine positions (Chan 1963, Flynn et al 1978, McManus and Calder 1978, Diaz et al 1980, Williams et al 1980, Hemminki 1983, Melzack 1991). One trial (Flynn et al 1978) found a significantly lower incidence of fetal heart rate abnormalities in the upright position, but other trials detected no significant differences in neonatal outcomes.
In conclusion, there is no evidence to support the encouragement of the supine position during the first stage of labour. The only exception is where the membranes have ruptured in the presence of a non-engaged fetal head. If and when the membranes are ruptured and the birth attendant has established a sufficient engagement of the fetal head, women should be free and encouraged to choose the position they prefer during labour. They will often change positions, as no position is comfortable for a long period of time.