Role and regulation of nitric oxide in the uterus during pregnancy and parturition

OBJECTIVE: To review English-language literature as it relates to the role and regulation of uterine nitric oxide (NO) during pregnancy and parturition, special emphasis being placed on the interactions of NO with other uterotonic agents. METHODS: A thorough literature review of the English-language using a Medline search was performed. RESULTS: Current data support the view that NO is generated in the uterus and inhibits uterine contractility. Gestation, parturition, steroid hormones, and prostaglandins modulate both the generation and the effects of NO on the uterus. The changes in NO and its effects are consistent with the theory that NO plays a role in uterine quiescence during pregnancy. A change in this system at term or preterm could play a role in inhibition of labor and delivery. CONCLUSION: Uterine NO may play a role in maintaining uterine quiescence during pregnancy. (C) 1998 by the Society for Gynecologic Investigation.