title: Serum 25-hydroxyvitamin D concentrations and treatment outcomes of women undergoing assisted reproduction.
abstract: BACKGROUND
  Vitamin D deficiency impairs fertility in animal models, but the role of vitamin D in human fertility or treatment of infertility is less clear.
  
  
  OBJECTIVE
  We examined the association between circulating 25-hydroxyvitamin D [25(OH)D] concentrations and the outcome in women undergoing assisted reproduction technologies (ARTs).
  
  
  METHODS
  We randomly selected 100 women undergoing infertility treatment with ART enrolled in an ongoing prospective cohort study who underwent 168 treatment cycles. Serum 25(OH)D concentrations were measured in samples collected from women between days 3 and 9 of gonadotropin treatment. Generalized linear mixed models were used to evaluate the association of 25(OH)D concentrations with ART outcomes while adjusting for potential confounders and accounting for repeated treatment cycles per woman.
  
  
  RESULTS
  Median (range) serum 25(OH)D concentrations were 86.5 (33.5-155.5) nmol/L. Ninety-one percent of participants consumed multivitamins. Serum 25(OH)D concentrations were positively related to fertilization rate. The adjusted fertilization rate for women in increasing quartiles of serum 25(OH)D were 0.62 (95% CI: 0.51, 0.72), 0.53 (95% CI: 0.43, 0.63), 0.67 (95% CI: 0.56, 0.76), and 0.73 (95% CI: 0.63, 0.80), respectively (P-trend = 0.03). This association persisted when analyses were restricted to women with serum 25(OH)D between 50 and 125 nmol/L when models were further adjusted for season of blood draw and when analyses were restricted to the first treatment cycle. However, 25(OH)D concentrations were unrelated to probability of pregnancy (P-trend = 0.83) or live birth after ART (P-trend = 0.47).
  
  
  CONCLUSIONS
  Vitamin D may be associated with higher fertilization rates, but this apparent benefit does not translate into higher probability of pregnancy or live birth. This trial was registered at www.clinicaltrials.gov as NCT00011713.
authors.affiliation: Departments of Nutrition.
authors.forename: Laura
authors.initials: L
authors.lastname: Abadia
authors.affiliation: Departments of Nutrition, Epidemiology.
authors.forename: Audrey J
authors.initials: AJ
authors.lastname: Gaskins
authors.affiliation: Departments of Nutrition, Epidemiology.
authors.forename: Yu-Han
authors.identifier: http://orcid.org/0000-0002-0904-7855
authors.initials: YH
authors.lastname: Chiu
authors.affiliation: Epidemiology, Biostatistics, and.
authors.forename: Paige L
authors.initials: PL
authors.lastname: Williams
authors.affiliation: Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA; Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; and.
authors.forename: Myra
authors.initials: M
authors.lastname: Keller
authors.affiliation: Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; and.
authors.forename: Diane L
authors.initials: DL
authors.lastname: Wright
authors.affiliation: Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; and.
authors.forename: Irene
authors.initials: I
authors.lastname: Souter
authors.affiliation: Epidemiology, Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA; Vincent Obstetrics and Gynecology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; and.
authors.forename: Russ
authors.initials: R
authors.lastname: Hauser
authors.affiliation: Departments of Nutrition, Epidemiology, Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA jchavarr@hsph.harvard.edu.
authors.forename: Jorge E
authors.initials: JE
authors.lastname: Chavarro
mesh_terms: D015652:25-Hydroxyvitamin D 2 / Q000097:blood*; D000328:Adult; D001900:Boston / Q000453:epidemiology; D002112:Calcifediol / Q000097:blood*; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D019587:Dietary Supplements; D005191:Family Characteristics; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007247:Infertility, Female / Q000097:blood / Q000150:complications / Q000453:epidemiology / Q000628:therapy*; D007248:Infertility, Male; D050498:Live Birth; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic; D013084:Sperm-Ovum Interactions; D014808:Vitamin D Deficiency / Q000150:complications* / Q000453:epidemiology; D014815:Vitamins / Q000008:administration & dosage
chemical_list: D014815:Vitamins; D015652:25-Hydroxyvitamin D 2; D002112:Calcifediol
keywords: assisted reproductive technologies; epidemiology; infertility; nutrition; vitamin D