title: Different SNP combinations in the GCH1 gene and use of labor analgesia.
abstract: BACKGROUND
  The aim of this study was to investigate if there is an association between different SNP combinations in the guanosine triphosphate cyclohydrolase (GCH1) gene and a number of pain behavior related outcomes during labor. A population-based sample of pregnant women (n = 814) was recruited at gestational week 18. A plasma sample was collected from each subject. Genotyping was performed and three single nucleotide polymorphisms (SNP) previously defined as a pain-protective SNP combination of GCH1 were used.
  
  
  RESULTS
  Homozygous carriers of the pain-protective SNP combination of GCH1 arrived to the delivery ward with a more advanced stage of cervical dilation compared to heterozygous carriers and non-carriers. However, homozygous carriers more often used second line labor analgesia compared to the others.
  
  
  CONCLUSIONS
  The pain-protective SNP combination of GCH1 may be of importance in the limited number of homozygous carriers during the initial dilation of cervix but upon arrival at the delivery unit these women are more inclined to use second line labor analgesia.
authors.affiliation: Department of Women's and Children's health, Uppsala University, Uppsala, Sweden.
authors.forename: Fatimah
authors.initials: F
authors.lastname: Dabo
authors.forename: Alfhild
authors.initials: A
authors.lastname: Grönbladh
authors.forename: Fred
authors.initials: F
authors.lastname: Nyberg
authors.forename: Inger
authors.initials: I
authors.lastname: Sundström-Poromaa
authors.forename: Helena
authors.initials: H
authors.lastname: Akerud
mesh_terms: D000328:Adult; D016362:Analgesia, Obstetrical; D005260:Female; D006136:GTP Cyclohydrolase / Q000235:genetics*; D006801:Humans; D048949:Labor Pain / Q000235:genetics*; D007747:Labor Stage, First; D007743:Labor, Obstetric; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy
chemical_list: D006136:GTP Cyclohydrolase