The Effect of Acupuncture on Uterine Contraction Induced by Oxytocin

Abstract

Pretern labor (PTL) is one of the main causes of fetal mortality and morbidity in obstetrical medicine. Current methods of treatment are not very effective and often have significant side effects. For this reason new methods of preventing PTL are currently being sought. In Western medicine the newest development is oxytocin antagonists. In Oriental medicine acupuncture and moxibustion are being utilized for the purpose of stopping PTL. The goals of this study were to determine if acupuncture in pregnant rats can suppress oxytocin induced uterine contractions and to compare these results with those inhibited by an oxytocin antagonist. Uterine contractions were induced by continuous infusion of exogenous oxytocin. The first fetus in one uterine horn near the ovarian end was removed and distilled water-filled catheter was inserted into that vacated amniotic sac to measure uterine contractions as intrauterine pressure changes. Two acupoints of Ho-Ku (LI-4) and San-Yin-Chiao (Sp-6) were selected for acupuncture and Kuan-Yüan (Co-4) was used for moxibustion. The oxytocin-induced uterine contractions were significantly suppressed by acupuncture on the LI-4 (p < 0.05), but not by Sp-6. Stimulation of Co-4 by moxibustion had no significant (p > 0.05) tocolytic effect. The administration of oxytocin antagonist eliminated all the uterine contractions induced by oxytocin. The application of acupuncture to re-stimulate the activity that was suppressed by the oxytocin antagonist did not produce any positive results. However, prostaglandins did cause the uterus to contract. In conclusion, acupuncture on LI-4 was found to suppress uterine contractions induced by oxytocin in the pregnant rat. If acupuncture is similarly effective in counteracting the effects of oxytocin in women, then this may an alternative medical treatment for women in preterm labor.