title: Is cervical length associated with maternal characteristics?
abstract: OBJECTIVE
  Women with a mid-trimester short cervical length (CL) are at increased risk for preterm delivery. Consequently, CL measurement is a potential screening tool to identify women at risk for preterm birth. Our objective was to assess possible associations between CL and maternal characteristics.
  
  
  METHODS
  A nationwide screening study was performed in which CL was measured during the standard anomaly scan among low risk women with a singleton pregnancy. Data on maternal height, pre-pregnancy weight, ethnicity, parity and gestational age at the time of the CL measurement were collected from January 2010 to December 2012. Univariable and multivariable linear regression analyses were performed to assess the relationship between CL and maternal characteristics.
  
  
  RESULTS
  We included 5092 women. The mean CL was 44.3mm. No association was found between CL and maternal height or gestational age of the measurement. Maternal weight was associated with CL (p=0.007, adjusted R(2) 0.03). Separate analysis for BMI did not change these results. Ethnicity, known in 2702 out of 5092 women, was associated with CL (mean CL in Caucasian women 45.0mm, Asian 43.9mm, Mediterranean 43.1mm, and African 41.8mm, p=0.003), as well as parity (mean CL multiparous 45.3mm, nulliparous 43.5mm, p<0.0001).
  
  
  CONCLUSIONS
  Shorter mid-trimester cervical length is associated with higher maternal weight, younger maternal age, nulliparity and non-Caucasian ethnicity, but not with maternal height.
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: a.j.vanderven@amc.uva.nl.
authors.forename: A J
authors.initials: AJ
authors.lastname: van der Ven
authors.affiliation: Department of Obstetrics and Gynaecology, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: m.vanos@vumc.nl.
authors.forename: M A
authors.initials: MA
authors.lastname: van Os
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: c.e.kleinrouweler@amc.uva.nl.
authors.forename: C E
authors.initials: CE
authors.lastname: Kleinrouweler
authors.affiliation: Department of Obstetrics and Gynaecology, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: cj.degroot@vumc.nl.
authors.forename: C J M
authors.initials: CJ
authors.lastname: de Groot
authors.affiliation: Department of Obstetrics and Gynaecology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: m.c.haak@lumc.nl.
authors.forename: M C
authors.initials: MC
authors.lastname: Haak
authors.affiliation: The Robinson Institute, School of Paediatrics and Reproductive Health, University of Adelaide, 5000 SA, Australia. Electronic address: b.w.mol@amc.uva.nl.
authors.forename: B W J
authors.initials: BW
authors.lastname: Mol
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: e.pajkrt@amc.uva.nl.
authors.forename: E
authors.initials: E
authors.lastname: Pajkrt
authors.affiliation: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, The Netherlands. Electronic address: b.m.kazemier@amc.uv.nl.
authors.forename: B M
authors.initials: BM
authors.lastname: Kazemier
mesh_terms: D000328:Adult; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D001837:Body Weights and Measures; D054791:Cervical Length Measurement; D002584:Cervix Uteri / Q000033:anatomy & histology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D010298:Parity; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D044469:Racial Groups
keywords: Cervical length; Maternal characteristics; Maternal height