title: Maternal plasma corticotrophin-releasing factor and urocortin levels in post-term pregnancies.
abstract: OBJECTIVE
  Corticotrophin-releasing factor (CRF) and urocortin are two placental neuropeptides that are involved in the mechanisms of labour by modulating myometrial activity. Maternal plasma levels of both CRF and urocortin are increased at term and preterm labour, whilst those of CRF are reduced in women who are destined to experience post-term delivery. The present study evaluated maternal plasma levels in term and post-term pregnancies out of labour.
  
  
  METHODS
  A group of healthy pregnant women was enrolled and subdivided as follows: (i) at term out of labour (n = 19; 276 +/- 0.7 days of gestation; samples collected at the time of elective caesarean section due to previous uterine surgery); (ii) post-term (n = 19; 291 +/- 1.4 days of gestation), from whom samples were collected before induction of labour.
  
  
  METHODS
  Urocortin and CRF measurements by radioimmunoassay; digital palpatory cervical examination and Bishop score computation; cervical length and funnelling presence assessment by transvaginal ultrasonography.
  
  
  RESULTS
  Maternal plasma CRF concentrations were significantly (P < 0.05) lower whilst those of urocortin were unchanged in post-term compared with term pregnancy. However, CRF and urocortin levels were both significantly (P < 0.05 and P < 0.001 respectively) higher in pregnancies delivered within 12 h of labour induction than in those that remained undelivered, and were significantly correlated with the induction-delivery interval (CRF: r = -0.676, P = 0.0015; urocortin: r = -0.783, P < 0.0001).
  
  
  CONCLUSIONS
  CRF and urocortin levels are decreased and unchanged, respectively, in post-term pregnancy when compared with term pregnancy. Both CRF and urocortin correlate with the time of labour onset after induction. Since CRF derives from the placenta, and urocortin from the fetus, the concerted expression of these neuropeptides appears to be relevant in determining the length of human gestation.
authors.affiliation: Department of Paediatrics, Obstetrics and Reproductive Medicine, University of Siena, Policlinico Le Scotte, viale Bracci 53100 Siena, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: Torricelli
authors.forename: Erika
authors.initials: E
authors.lastname: Ignacchiti
authors.forename: Alessia
authors.initials: A
authors.lastname: Giovannelli
authors.forename: Angelica
authors.initials: A
authors.lastname: Merola
authors.forename: Elisa
authors.initials: E
authors.lastname: Scarpetti
authors.forename: Giulia
authors.initials: G
authors.lastname: Calonaci
authors.forename: Enrico
authors.initials: E
authors.lastname: Picciolini
authors.forename: Pasquale
authors.initials: P
authors.lastname: Florio
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Reis
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Linton
authors.forename: Felice
authors.initials: F
authors.lastname: Petraglia
mesh_terms: D000328:Adult; D003346:Corticotropin-Releasing Hormone / Q000097:blood*; D005260:Female; D006801:Humans; D007751:Labor, Induced; D011247:Pregnancy; D011273:Pregnancy, Prolonged / Q000097:blood*; D054832:Urocortins
chemical_list: D054832:Urocortins; D003346:Corticotropin-Releasing Hormone