title: Correlation of first-trimester fetal crown-rump length with outcome of pregnancy and birth weight.
abstract: OBJECTIVE
  To examine the association of crown-rump length (CRL) in the first trimester with low birth weight and adverse pregnancy outcome.
  
  
  METHODS
  In a prospective cross-sectional study, CRL was measured in 876 healthy pregnant women undergoing ultrasound evaluation between 9 and 14 weeks of gestation. Birth weight and pregnancy outcomes were analyzed for the 544 participants who met the study criteria.
  
  
  RESULTS
  Low (<2500 g) and high (>4000 g) birth weights were correlated with the difference between actual and expected CRL expressed in days of gestation, but no correlation was found between the difference between actual and expected CRL and premature delivery. Low birth weight (P=0.005) and abortion (P=0.03) were also correlated with the difference between actual and expected CRL.
  
  
  CONCLUSIONS
  Routinely measuring CRL during the first trimester to detect CRLs shorter than expected for gestational age could be useful to obstetricians. Anticipating a low birth weight and being warned about the possibility of abortion would enable them to manage prenatal care and delivery more appropriately.
authors.affiliation: Department of Obstetrics and Gynecology, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Homeira
authors.initials: H
authors.lastname: Vafaei
authors.forename: Alamtaj
authors.initials: A
authors.lastname: Samsami
authors.forename: Jaleh
authors.initials: J
authors.lastname: Zolghadri
authors.forename: Azam
authors.initials: A
authors.lastname: Hosseini-Nohadani
mesh_terms: D000293:Adolescent; D000328:Adult; D001724:Birth Weight; D003430:Cross-Sectional Studies; D018568:Crown-Rump Length; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008875:Middle Aged; D011247:Pregnancy; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D011295:Prenatal Care / Q000379:methods*; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal; D055815:Young Adult