title: Maternal IGF1 and IGF1R polymorphisms and the risk of spontaneous preterm birth.
abstract: BACKGROUND
  The insulin-like growth factor (IGF) pathway was involved in the occurrence of spontaneous preterm birth (SPTB), but little is known regarding the relationship between genetic variations in IGF pathway and the risk of SPTB. We aimed to investigate the associations of IGF1 rs972936 and IGF1 receptor (IGF1R) rs2229765 polymorphisms with SPTB risk in a Chinese population.
  
  
  METHODS
  A total of 114 cases of SPTB and 250 controls of term delivery were included from Guangzhou Women and Children's Medical Center, China. The odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated using multivariate logistic regression.
  
  
  RESULTS
  We found that the GA and GA/AA genotypes of IGF1 rs972936 were associated with an increased risk of SPTB, and the adjusted ORs (95% CI) were 1.74 (1.01-3.02) and 1.75 (1.04-2.93) respectively. Women carrying GA and GA/AA genotypes of IGF1R rs2229765 had a reduced risk compared to those with the GG genotype (0.60 [0.37-0.98] and 0.64 [0.40-1.00] respectively). There were significant interactions between IGF1 rs972936 and GDM status (P for interaction=.02), as well as between IGF1R rs2229765 and pre-pregnancy BMI (P for interaction <.001) on the risk of SPTB.
  
  
  CONCLUSIONS
  Our findings suggest that polymorphisms of IGF1 rs972936 and IGF1R rs2229765 were associated with the risk of SPTB in Chinese pregnant women and these effects depend on the maternal metabolic status.
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Jian-Rong
authors.initials: JR
authors.lastname: He
authors.affiliation: Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Yu-Mian
authors.initials: YM
authors.lastname: Lai
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Hui-Hui
authors.initials: HH
authors.lastname: Liu
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Guang-Jian
authors.initials: GJ
authors.lastname: Liu
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Wei-Dong
authors.initials: WD
authors.lastname: Li
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xue-Jiao
authors.initials: XJ
authors.lastname: Fan
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xue-Ling
authors.initials: XL
authors.lastname: Wei
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Xia
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Ya-Shu
authors.initials: YS
authors.lastname: Kuang
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xiao-Dan
authors.initials: XD
authors.lastname: Liu
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Nian-Nian
authors.initials: NN
authors.lastname: Chen
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Jin-Hua
authors.initials: JH
authors.lastname: Lu
authors.affiliation: Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Qiao-Zhu
authors.initials: QZ
authors.lastname: Chen
authors.affiliation: Department of Obstetrics and Gynecology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Wei-Bi
authors.initials: WB
authors.lastname: Mai
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Hui-Min
authors.initials: HM
authors.lastname: Xia
authors.affiliation: Division of Birth Cohort Study, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xiu
authors.initials: X
authors.lastname: Qiu
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002681:China; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D047928:Premature Birth / Q000453:epidemiology* / Q000235:genetics*; D017526:Receptor, IGF Type 1 / Q000235:genetics*
chemical_list: C583557:IGF1 protein, human; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1
keywords: 
  IGF1
  ; 
  IGF1R
  ; polymorphism; spontaneous preterm birth; susceptibility