Pethidine compared with meptazinol during labour. A prospective randomised double-blind study in 1100 patients

A randomised double-blind comparison of pethidine and meptazinol used as analgesics in labour was carried out in 1,100 consecutive women who would normally have received intramuscular pethidine. Pain assessments at 30-minute intervals were made independently by patients and midwives. Maternal and neonatal side effects were noted. The babies' requirements for resuscitation and weight changes in the first 5 days were studied. There was no difference in the analgesia provided by the two drugs; the pattern of side effects was similar, but the incidence of vomiting was greater following meptazinol administration. The babies in the two groups were similar with respect to resuscitation received, weight gains or losses and the incidence of clinical neonatal jaundice. The most striking findings were the poor quality of pain relief experienced by both groups following parenteral analgesics and the high incidence of side effects.