Epidural analgesia in labour and maternal posture.

The effect of maternal position in the period immediately following epidural administration on analgesia and side effects was examined during labour. Patients were randomly allocated to two groups and were either turned from left to right lateral position within 5 minutes of bupivacaine administration (n = 35), or kept in the supine position, modified as appropriate, until pain relief or side effects indicated a change (n = 35). There was no significant difference between the two groups in onset or duration of analgesia, the need for supplements or in absorption of bupivacaine. Circulatory disturbances, all mild and transient, were seen in 14 patients (eight lateral, six supine). There was no significant difference between the two groups either in the frequency of hypotension (four lateral, five supine) or of fetal heart deterioration (four lateral, three supine). However motor block occurred in 15 of the lateral group and five supine (p less than 0.02). Such differences are not thought sufficient to counterbalance the potential circulatory disadvantage of the supine position.