title: Prediction of preterm delivery using changes in serum relaxin in low risk pregnancies.
abstract: OBJECTIVE
  To examine serum relaxin as a predictor of spontaneous preterm delivery.
  
  
  METHODS
  A prospective study of 2846 women with singleton pregnancies, from which a matched case-control study (84 cases of spontaneous preterm delivery before 37 weeks gestation and 175 controls) and a cohort (84 preterm and 399 term deliveries) were extracted.
  
  
  RESULTS
  In the women with a subsequent preterm delivery the relaxin level decreased by 0.9% per week as compared to 1.9% per week (t-test, p=0.004) in the women with term deliveries. From the cohort the course of S-relaxin during pregnancy in both preterm and term deliveries were fitted and graphed. S-relaxin level was raised in women who were hormonally stimulated to obtain pregnancy (p=0.0001), and lower in women with pre-pregnancy overweight (BMI> or =25, p=0.01) as well as in women, who had previously been pregnant (p=0.008). A longitudinal adjusted model for the prediction of preterm delivery based on the change in S-relaxin was established.
  
  
  CONCLUSIONS
  S-relaxin levels decrease less rapidly in women who subsequently deliver preterm; this results in elevated S-relaxin levels in the second and the third trimesters.
authors.affiliation: NANEA, Institute for Public Health, Department of Epidemiology, University of Aarhus, Vennelyst Boulevard 6, 8000 Aarhus C, Denmark. iv@soci.au.dk
authors.forename: Ida
authors.initials: I
authors.lastname: Vogel
authors.forename: Poul
authors.initials: P
authors.lastname: Thorsen
authors.forename: Heidi Holmager
authors.initials: HH
authors.lastname: Hundborg
authors.forename: Niels
authors.initials: N
authors.lastname: Uldbjerg
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D008962:Models, Theoretical; D011237:Predictive Value of Tests; D011247:Pregnancy; D011264:Pregnancy Trimesters; D047928:Premature Birth / Q000097:blood*; D011446:Prospective Studies; D012065:Relaxin / Q000097:blood*; D012307:Risk Factors
chemical_list: D012065:Relaxin