Intravenous nitroglycerin for rapid uterine relaxation

Acta Obstet Gynecol Scand. 1998 Jan;77(1):50-3. doi: 10.1034/j.1600-0412.1998.770111.x.


Background: To investigate the effect of nitroglycerin in vitro and in vivo on human uterine contractile activity.

Methods: In vitro myometrial strips were obtained from six pregnant women at term who underwent elective cesarean section. The biopsies were mounted in tissue baths. After spontaneous or oxytocin-induced activity had been accomplished, nitroglycerin in various concentrations was added to the baths and the effects were continuously registered. In vivo, in an open study nitroglycerin was administered as a bolus injection of 100-200 micrograms intravenously to 32 women at cesarean section when uterine relaxation was urgently needed; to 22 other women after vaginal delivery for facilitation of manual removal of retained placentas, and to one patient at vaginal delivery of premature twins.

Results: In vitro nitroglycerin induced a dose-dependent inhibition of spontaneous as well as oxytocin-induced myometrial contractile activity. Complete muscular relaxation was obtained at a concentration of 25-50 micrograms/ml. In vivo all patients had rapid effective uterine relaxation after intravenous injection of 100-200 micrograms nitroglycerin.

Conclusion: Nitroglycerin administered intravenously seems to be a rapid and effective uterine muscle relaxant agent without overt adverse effects on mother or fetus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cesarean Section
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • In Vitro Techniques
  • Injections, Intravenous
  • Muscle Relaxation / drug effects
  • Myometrium / drug effects
  • Myometrium / physiology
  • Nitroglycerin / administration & dosage*
  • Placenta, Retained / therapy
  • Pregnancy
  • Uterine Contraction / drug effects*


  • Nitroglycerin