title: Urinary cyclic guanosine 3',5'-monophosphate and cyclic adenosine 3',5'-monophosphate changes in spontaneous and induced onset active labor.
abstract: BACKGROUND
  The aim of this prospective, randomized study was to investigate the changes in urinary cyclic guanosine 3',5'-monophosphate (cGMP) and cyclic adenosine 3',5'-monophosphate (cAMP) between the latent and the active phases of spontaneous and prostaglandin E(1) (PGE(1))-induced labor.
  
  
  METHODS
  Seventy singleton pregnant women at 36-41(+) weeks' gestation without signs of fetal distress were enrolled. The first group consisted of 35 pregnant women in whom labor was induced by PGE(1) applied intravaginally. The second group consisted of 35 women who had spontaneous active labor. Clinical data of the two groups were assessed as labor progressed.
  
  
  RESULTS
  After the onset of active labor, urinary cGMP/creatinine (U cGMP/Cr) decreased in both groups with the percentage decline of 35.2 and 9.7, respectively, but this difference was only significant in the PGE(1)-induced group (P=0.033). After the onset of active labor, urinary cAMP/creatinine (U cAMP/Cr) decreased in both groups with the percentage decline of 36.5 and 15.6, respectively, but this difference was only significant in the PGE(1)-induced group (P=0.001). The duration of the latent phase was significantly shortened in the PGE(1)-induced group compared with the spontaneous labor group (P<0.05).
  
  
  CONCLUSIONS
  Decreased U cGMP/Cr and U cAMP/Cr may be a transition from the latent to the active phase in PGE(1)-induced labor. Our results suggest that U cGMP/Cr and U cAMP/Cr can serve as easily obtained secondary messenger markers of myometrial contractility and cervical ripening at the onset of active labor. The NO-cGMP system and the G-protein alpha-cAMP system in the human uterus may concomitantly contribute to uterine quiescence during pregnancy and show downregulation in U cGMP/Cr and U cAMP/Cr at the initiation of active labor.
authors.affiliation: Department of Obstetrics and Gynecology, E-Da Hospital, I-Shou, University, Kao-Shoung County, Taiwan.
authors.forename: Da-Chung
authors.initials: DC
authors.lastname: Chen
authors.forename: Shyng-Shiou F
authors.initials: SS
authors.lastname: Yuan
authors.forename: Her-Young
authors.initials: HY
authors.lastname: Su
authors.forename: Shin-Chieh
authors.initials: SC
authors.lastname: Lo
authors.forename: Shin-Sia
authors.initials: SS
authors.lastname: Ren
authors.forename: Gwo-Jang
authors.initials: GJ
authors.lastname: Wu
mesh_terms: D000328:Adult; D000242:Cyclic AMP / Q000652:urine*; D006152:Cyclic GMP / Q000652:urine*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007751:Labor, Induced / Q000379:methods*; D007743:Labor, Obstetric / Q000652:urine*; D016595:Misoprostol; D009569:Nitric Oxide / Q000378:metabolism; D010120:Oxytocics; D018579:Patient Selection; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D011863:Radioimmunoassay
chemical_list: D010120:Oxytocics; D016595:Misoprostol; D009569:Nitric Oxide; D000242:Cyclic AMP; D006152:Cyclic GMP