Impact of the L-arginine/nitric oxide system in pregnancy.

Nitric Oxide (NO) recently becomes of clinical interest because of its relaxant effects on smooth muscle. In addition to endothelial cells, also myometrial cells contain the enzyme implicated in the NO production. This review is aimed toward those studies concerned with the production, metabolism, and effects of NO that could be relevant for the obstetricians. The potential clinical interest of such information covers the main areas of pregnancy complications, namely preterm delivery, preeclampsia, and intrauterine growth retardation. Moreover, original data are included in order to support the therapeutical implications of the manipulation of L-arginine-NO system in case of pregnancy disorders.