ABSTRACT
One of the basic principles of modern obstetrics is to provide adequate analgesia. An analgesic should have potent analgesic efficacy and minimal side effects to be suitable for pain relief during labour. The aim of this study was to evaluate and compare the analgesic efficacy and adverse effects of tramadol and pethidine on labour pain, labour duration, apgar score of the infants and maternal complications in primiparous women. This was a triple-blind randomized control trial. 30 full term parturient women were randomly assigned to one of tramadol or pethidine groups. Inclusion criteria were full term primiparous women without high risk pregnancy in active phase of labour, with 4 cm dilatation of cervix. Lack of induction of delivery, lack of pregnancy complications and drug reactions were regarded as other inclusion criteria. In active phase of delivary vital signs of the parturient women recorded. The pain was measured by means of NRS score. Group I received 50 mg pethedine; group II, 50 mg tramadol in 200 cc Ringer solution, intravenously. The vital signs and pain were reassessed after one hour. The mothers and their fetuses were under control for potential complications. Collected data were introduced into SPSS soft ware and analyzed by means of t-test and X[2]. p<0.05 was regarded statistically significant. There was no significant difference in relation to age, maternal weight, maternal educational status, gestational age and infant's weight between the two groups. There was no significant difference between the decrease in the mean systolic and diastolic blood pressures in the two groups. Maternal Side effects such as nausea, vomiting and drowsiness occurred more frequently in pethidine group [p 0.05]. The mean values of pain reduction assessed by VAS score were 1.28 +/- 1.63 for pethidine group and 1.00 +/- 1.30 for tramadol group] p < 0.05]. We conclude that pethidine has more analgesic effect than tramadol on labour pain but frequency of side effects such as nausea and vomiting was higher with pethidine administration. Both drugs can cause shortening of active phase of labour. Apgar score was not influenced by any of the two drugs