title: Pre-pregnancy caffeine and caffeinated beverage intake and risk of spontaneous abortion.
abstract: OBJECTIVE
  To investigate the relation between pre-pregnancy caffeine and caffeinated beverage intake and risk of spontaneous abortion (SAB).
  
  
  METHODS
  Our prospective cohort study included 15,590 pregnancies from 11,072 women with no history of SAB in the Nurses' Health Study II (1991-2009). Beverage intake was assessed every 4 years using a validated questionnaire. Pregnancies were self-reported with case pregnancies lost spontaneously at <20 weeks gestation. Multivariable log-binomial regression models with generalized estimating equations were used to estimate the relative risks (RRs) and 95 % confidence intervals (CIs).
  
  
  RESULTS
  There was a positive linear trend across categories of pre-pregnancy caffeine intake and risk of SAB such that women consuming >400 mg/day had 1.11 (95 % CI 0.98, 1.25) times the risk of SAB compared to women consuming <50 mg/day (p trend = 0.05). Total coffee intake had a positive, linear association with SAB. Compared to women with no pre-pregnancy coffee intake, women consuming ≥4 servings/day had a 20 % (6, 36 %) increased risk of SAB (p trend = 0.01). There was no difference in the association between caffeinated and decaffeinated coffee and risk of SAB. Pre-pregnancy intake of caffeinated tea, caffeinated soda, and decaffeinated soda had no association with SAB.
  
  
  CONCLUSIONS
  Pre-pregnancy coffee consumption at levels ≥4 servings/day is associated with increased risk of SAB, particularly at weeks 8-19.
authors: Department of Nutrition, Harvard T.H. Chan School of Public Health, Building II 3rd Floor, 655 Huntington Ave, Boston, MA, 02115, USA. agaskins@hsph.harvard.edu.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA. agaskins@hsph.harvard.edu.
authors: Audrey J
authors: AJ
authors: Gaskins
authors: Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Department of Medicine, Connors Center for Women's Health and Gender Biology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Janet W
authors: JW
authors: Rich-Edwards
authors: Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors: Paige L
authors: PL
authors: Williams
authors: Vincent Obstetrics and Gynecology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
authors: Thomas L
authors: TL
authors: Toth
authors: Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Department of Obstetrics, Gynecology and Reproductive Biology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.|Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors: Stacey A
authors: SA
authors: Missmer
authors: Department of Nutrition, Harvard T.H. Chan School of Public Health, Building II 3rd Floor, 655 Huntington Ave, Boston, MA, 02115, USA.|Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
authors: Jorge E
authors: JE
authors: Chavarro
mesh_terms: D000022:Abortion, Spontaneous / Q000139:chemically induced / Q000453:epidemiology*; D000328:Adult; D001628:Beverages / Q000009:adverse effects / Q000032:analysis; D015992:Body Mass Index; D002110:Caffeine / Q000008:administration & dosage* / Q000009:adverse effects* / Q000032:analysis; D002253:Carbonated Beverages / Q000009:adverse effects / Q000032:analysis; D003069:Coffee / Q000009:adverse effects; D004032:Diet; D005260:Female; D005865:Gestational Age; D006801:Humans; D016742:Preconception Care; D011247:Pregnancy; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013662:Tea / Q000009:adverse effects / Q000737:chemistry
chemical_list: D003069:Coffee; D013662:Tea; D002110:Caffeine
keywords: Caffeine; Coffee; Miscarriage; Pregnancy; Spontaneous abortion