Aim: The aim of this study was to evaluate the effectiveness of meperidine, administered during the first stage of labor in patients with uterine dystocia, on the duration of labor and neonatal acid-base status at birth.
Material and methods: We randomly assigned 240 nulliparous women with a singleton pregnancy at term who were diagnosed with uterine dystocia in labor at 4-6-cm cervical dilatation to receive either a single dose of 50 mg meperidine in 10 mL of saline (slow intravenous injection over 2 min) or 10 mL of isotonic saline (control group). The primary outcome measures were duration of labor (from the time of beginning of the intervention to the time of the expulsion of the fetal head) and umbilical cord arterial acid-base status.
Results: The evidence revealed no statistically significant difference between the two groups in length of labor (188.2 ± 92.3 min in the meperidine group compared to 205.4 ± 96.1 min in the placebo group, P = 0.159). The pH of the umbilical cord arterial samples was lower in the meperidine group than in the control group, although the difference was not statistically significant (P = 0.089).
Conclusion: Because of the absence of any beneficial effect of meperidine on uterine dystocia, its use in labor should be limited to pain relief in the absence of epidural analgesia.
© 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.