title: Prevalence and patterns of nitrosatable drug use among U.S. women during early pregnancy.
abstract: BACKGROUND
  Experimental evidence indicates that certain drugs, that are secondary or tertiary amines or amides, form N-nitroso compounds in the presence of nitrite in an acidic environment. Nitrosatable drugs have been associated with birth defects in a few epidemiologic studies. This study describes the prevalence and patterns of nitrosatable drug use among U.S. women during early pregnancy and examines maternal factors associated with such use.
  
  
  METHODS
  Data were analyzed from the National Birth Defects Prevention Study and included 6807 mothers who gave birth to babies without major congenital malformations during 1997 to 2005. Information was collected by telephone interview about medication use, demographic factors, and maternal health. Drugs taken during the first trimester were classified according to nitrosatability, amine and amide functional groups, and primary indication of use.
  
  
  RESULTS
  Approximately 24% of the women took one or more nitrosatable drugs during the first trimester, including 12.4%, 12.2%, and 7.6% who respectively took secondary amines, tertiary amines, or amides. Five of the ten most commonly taken drugs were available over the counter. Women who were non-Hispanic white (29.5%), with 1 year or more college education (27.3%) or 40 years or older (28.8%) had the highest prevalence of use. Supplemental vitamin C, an inhibitor of nitrosation, was not taken by 41.6% and 19.3% of nitrosatable drug users during the first and second months of pregnancy, respectively.
  
  
  CONCLUSIONS
  In this U.S. population, ingestion of drugs classified as nitrosatable was common during the first trimester of pregnancy, especially among non-Hispanic white, more educated, and older mothers.
authors.affiliation: Texas A&M Health Science Center, School of Rural Public Health, College Station, Texas. jdbrender@srph.tamhsc.edu
authors.forename: Jean D
authors.initials: JD
authors.lastname: Brender
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Kelley
authors.forename: Martha M
authors.initials: MM
authors.lastname: Werler
authors.forename: Peter H
authors.initials: PH
authors.lastname: Langlois
authors.forename: Lucina
authors.initials: L
authors.lastname: Suarez
authors.forename: Mark A
authors.initials: MA
authors.lastname: Canfield
mesh_terms: D000588:Amines / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000494:pharmacology*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008423:Maternal Age; D009573:Nitrites / Q000008:administration & dosage*; D015538:Nitrosation; D009603:Nitroso Compounds / Q000008:administration & dosage*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D011261:Pregnancy Trimester, First; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D044465:White People
chemical_list: D000588:Amines; D009573:Nitrites; D009603:Nitroso Compounds; D001205:Ascorbic Acid