title: Decreased serum vitamin D levels in early spontaneous pregnancy loss.
abstract: Effects of vitamin D deficiency in pregnancy have been associated with some adverse pregnancy outcomes. The objective of this study was to analyze the relationship between vitamin D deficiency in childbearing aged women and pregnancy loss (PL) in the first trimester.
  
  
  
  This is a cross-sectional study. Plasma was collected from 60 nulliparous women with singleton at 7-9 weeks of gestation (30 with viable gestation and 30 with PL) and 60 non-gravid childbearing aged women (30 with a successful pregnancy history, and 30 with one or more spontaneous first-trimester PL history). Quantitation of serum 25-hydroxyvitamin D (25(OH)D) and 25-hydroxyvitamin D-1 alpha hydroxylase (CYP27B1) was assayed.
  
  
  
  By pregnancy/non-gravid, normal pregnant women had higher 25(OH)D (49.32 μg/l) and CYP27B1 (82.00 pg/ml) than PL women (34.49 μg/l and 37.87 pg/ml, both P<0.01); the non-gravid women with a successful pregnancy history also had higher 25(OH)D (39.56 μg/l) and CYP27B1 (39.04 pg/ml) than women with PL history (12.30 μg/l and 12.35 pg/ml, both P<0.01). The 96.7% of non-gravid women with PL history and 43.3% of PL women had serum 25(OH)D concentrations below 30 μg/l. There was a strong association between low vitamin D levels and PL (odds ratio 1.71; 95% confidence interval: 1.2-2.4, P<0.001). The regression analyses showed that PL was significantly inversely correlated with 25(OH)D (P<0.01) and CYP27B1 levels (P<0.01).
  
  
  
  Vitamin D deficiency associated with PL in the first trimester of pregnancy. Decreased serum vitamin D levels among childbearing aged women with the failed clinical pregnancies history may predispose to increased risk for PL.
authors.affiliation: Department of Obstetrics & Gynecology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.|Department of Maternal Health Care, Maternal and Child Health Hospital of Shaanxi Province, Xi'an, China.
authors.forename: W
authors.initials: W
authors.lastname: Hou
authors.affiliation: Department of Obstetrics & Gynecology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
authors.forename: X-T
authors.initials: XT
authors.lastname: Yan
authors.affiliation: Department of Maternal Health Care, Maternal and Child Health Hospital of Shaanxi Province, Xi'an, China.
authors.forename: C-M
authors.initials: CM
authors.lastname: Bai
authors.affiliation: Department of Obstetrics & Gynecology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.|Department of Obstetrics & Gynecology, Fourth hospital of Xi'an City, Xi'an, China.
authors.forename: X-W
authors.initials: XW
authors.lastname: Zhang
authors.affiliation: Laboratory Department, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
authors.forename: L-Y
authors.initials: LY
authors.lastname: Hui
authors.affiliation: Department of Obstetrics & Gynecology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
authors.forename: X-W
authors.initials: XW
authors.lastname: Yu
mesh_terms: D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase / Q000097:blood; D000022:Abortion, Spontaneous / Q000097:blood / Q000209:etiology*; D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005865:Gestational Age; D020073:Gravidity; D006801:Humans; D016017:Odds Ratio; D010298:Parity; D011247:Pregnancy / Q000097:blood; D011248:Pregnancy Complications / Q000097:blood*; D011256:Pregnancy Outcome; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D; D015090:25-Hydroxyvitamin D3 1-alpha-Hydroxylase