title: [Reproductive risk factors of breast cancer in patients attended at a second level urban hospital].
abstract: OBJECTIVE
  To evaluate the implication of reproductive risk factors for breast cancer of patients at a breast clinic of a second level urban hospital.
  
  
  METHODS
  Women with breast cancer and randomly selected age-matched control subjects were evaluated. Age, age of menarche and menopause, age of first full term pregnancy, number of pregnancies, lactation, family history of breast cancer and family history of other cancers were analyzed.
  
  
  RESULTS
  Sixty-six cases with breast cancer and 132 controls were study. Cases were older at first full term pregnancy (25.8 +/- 6.4 vs 23.3 +/- 5 years old, p = 0.01) and presented frequently first full term pregnancies after 30 years old (19.6 vs. 6%, p = 0.01); these differences also were significative for cases of 50 years or older. Cases younger than 50 years old had short lifetime lactation (11.5 +/- 8.2 vs. 27 +/- 30 months, p < 0.001), and few presented lactation longer than 12 months (27.8 vs 55.8%, p = 0.02).
  
  
  CONCLUSIONS
  In this research the most important breast cancer risk factor for women older than 50 years old was the age of first full term pregnancy. For women younger than 50 years old periods of lifetime lactation shorter than 12 months seems a risk factor.
authors.affiliation: Servicio de clínica de mama, Hospital General Tacuba, DF México. cortizmendoza@yahoo.com.mx
authors.forename: Carlos Manuel
authors.initials: CM
authors.lastname: Ortiz Mendoza
authors.forename: Elsa A
authors.initials: EA
authors.lastname: Galván Martínez
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology*; D016022:Case-Control Studies; D005260:Female; D006786:Hospitals, Urban / Q000706:statistics & numerical data; D006801:Humans; D007774:Lactation; D008572:Menarche; D008593:Menopause; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D009369:Neoplasms / Q000235:genetics; D010298:Parity; D011247:Pregnancy; D017584:Reproductive History; D012307:Risk Factors