title: Comparison of cervical length in adult and adolescent nulliparae at mid-gestation.
abstract: OBJECTIVE
  To compare cervical lengths of adolescents and adults in mid-gestation.
  
  
  METHODS
  An analytical, observational, and cross-sectional study.
  
  
  METHODS
  Public health system in the city of Blumenau, Brazil.
  
  
  METHODS
  Primigravidae adolescents under the age of 16 and adults over age 20 (n = 40/group) were systematically sampled.
  
  
  METHODS
  Cervical measurements were performed between 21 and 24 weeks of gestation through transvaginal ultrasonography using a previously validated method.
  
  
  METHODS
  Mean cervical length (Mann-Whitney test) and percentage of cervices below 25 mm (Fisher exact test).
  
  
  RESULTS
  For adolescents and adults, average uterine cervix lengths were 28 ± 6.6 mm 33 ± 4.1 mm (P < .0001), respectively, and the proportion of cervixes below 25 mm were 27.5% and 7.5% (P < .02), respectively. In addition, adolescents had significantly lower gynecologic age, education, and family income than adults.
  
  
  CONCLUSIONS
  Primigravida adolescents under the age of 16 have shorter cervices than adults, and a higher percentage of adolescents have cervices shorter than 25 mm. This may be associated with the higher risk of preterm birth observed in adolescents and suggests that this population requires special attention in prenatal care.
authors.affiliation: Faculty of Medical Science, University of Campinas, and Department of Medicine, Health Sciences Center, Regional University of Blumenau, Blumenau, Brazil. carladagostini@gmail.com
authors.forename: Carla
authors.initials: C
authors.lastname: D'Agostini
authors.forename: Melissa
authors.initials: M
authors.lastname: de Oliveira
authors.forename: Lilia
authors.initials: L
authors.lastname: D'Souza-Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002584:Cervix Uteri / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D010298:Parity; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011253:Pregnancy in Adolescence; D047928:Premature Birth / Q000209:etiology; D012307:Risk Factors; D014463:Ultrasonography; D055815:Young Adult
keywords: Cervical length measurement; Pregnancy in adolescence; Premature birth