title: Maternal thyroid disease in the Danish National Birth Cohort: prevalence and risk factors.
abstract: OBJECTIVE
  Thyroid disorders are common in women of reproductive age, but the exact burden of disease before, during and after a pregnancy is not clear. We describe the prevalence of thyroid disease in women enrolled in the Danish National Birth Cohort (DNBC) and investigate some of its risk factors.
  
  
  METHODS
  Population-based study within the DNBC, which included 101,032 pregnancies (1997-2003).
  
  
  METHODS
  We studied women enrolled in the DNBC who gave birth to a live-born child. Information on maternal thyroid disease (hyperthyroidism, hypothyroidism, benign goiter/nodules, thyroid cancer, and other) before, during and up to 5 years after the woman's first pregnancy in the cohort was obtained from self-report (telephone interview in median gestational week 17) and from nationwide registers on hospital diagnosis of thyroid disease/thyroid surgery (from 1977) and prescriptions of thyroid drugs (from 1995).
  
  
  RESULTS
  Of the 77,445 women studied, 3018 (3.9%) were identified with an onset of thyroid disease before (2.0%), during (0.1%) or in the 5-year period after the pregnancy (1.8%). During the pregnancy, 153 (0.2%) women received antithyroid drugs and 365 (0.5%) received thyroid hormone for hypothyroidism (83 after previous hyperthyroidism, 42 after previous surgery for benign goiter/nodules or thyroid cancer). Significant risk factors for maternal thyroid disease were age, parity, origin, iodine intake, smoking, alcohol, and BMI.
  
  
  CONCLUSIONS
  Around 4% of Danish pregnant women had either a history of thyroid disease or thyroid disease during pregnancy or were diagnosed with thyroid disease for the first-time in the years following a pregnancy. The spectrum of thyroid disease was influenced by demographic and environmental factors.
authors.affiliation: Departments of EndocrinologyClinical BiochemistryAalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, DenmarkDepartment of Clinical EpidemiologyAarhus University Hospital, 8000 Aarhus, DenmarkDepartment of Clinical MedicineAalborg University, 9000 Aalborg, Denmark Departments of EndocrinologyClinical BiochemistryAalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, DenmarkDepartment of Clinical EpidemiologyAarhus University Hospital, 8000 Aarhus, DenmarkDepartment of Clinical MedicineAalborg University, 9000 Aalborg, Denmark stine.a@rn.dk.
authors.forename: Stine Linding
authors.initials: SL
authors.lastname: Andersen
authors.affiliation: Departments of EndocrinologyClinical BiochemistryAalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, DenmarkDepartment of Clinical EpidemiologyAarhus University Hospital, 8000 Aarhus, DenmarkDepartment of Clinical MedicineAalborg University, 9000 Aalborg, Denmark.
authors.forename: Jørn
authors.initials: J
authors.lastname: Olsen
authors.affiliation: Departments of EndocrinologyClinical BiochemistryAalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, DenmarkDepartment of Clinical EpidemiologyAarhus University Hospital, 8000 Aarhus, DenmarkDepartment of Clinical MedicineAalborg University, 9000 Aalborg, Denmark Departments of EndocrinologyClinical BiochemistryAalborg University Hospital, Sdr. Skovvej 15, 9000 Aalborg, DenmarkDepartment of Clinical EpidemiologyAarhus University Hospital, 8000 Aarhus, DenmarkDepartment of Clinical MedicineAalborg University, 9000 Aalborg, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Laurberg
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D015995:Prevalence; D012042:Registries; D012307:Risk Factors; D013959:Thyroid Diseases / Q000453:epidemiology*