title: First-trimester reference centiles of fetal biometry in Indian population.
abstract: OBJECTIVE
  To create crown-rump length (CRL)-based biometric chart for fetus in the first trimester among the Indian population.
  
  
  METHODS
  Cross-sectional data were obtained from 400 singleton pregnancies between 11 and 14 weeks gestation with a normal outcome. Linear regression models were constructed; the mean and SD were derived as a function of CRL.
  
  
  RESULTS
  There was a positive correlation of CRL with nuchal translucency (NT) (y = 0.0102x + 0.6307 R2=0.1177), biparietal diameter (BPD) (BPD = 0.032*CRL +0.185 R2=0.765), occipito-frontal diameter (OFD), lateral ventricular diameter (LV), abdominal circumference (AC) (AC = 0.944*CRL +9.684 R2=0.668), femur length (FL) (FL = 0.222*CRL -4.734 R2=0.661), fetal weight (FW) (FW = 1.328*CRL -10.41 R2=0.662). The regression models and centile charts of NT, BPD, OFD, LV, AC, and FW were constructed. Taking FW as the independent variable, a linear equation of BPD, AC, and FL to calculate weight was constructed.
  
  
  CONCLUSIONS
  The first-trimester centile charts of fetal parameters can be used as a reference for Indian population in the determination of gestational age or other adverse outcomes.
authors.affiliation: a Department of Obstetrics & Gynecology , LHMC , New Delhi , India.
authors.forename: Manisha
authors.initials: M
authors.lastname: Kumar
authors.affiliation: b Department of Statistics, Lady Sri Ram College , New Delhi , India.
authors.forename: Ravi
authors.initials: R
authors.lastname: Vajala
authors.affiliation: c Department of Biochemistry, LHMC , New Delhi , India.
authors.forename: Karuna
authors.initials: K
authors.lastname: Sharma
authors.affiliation: d Scientist Group E , ICMR , New Delhi , India.
authors.forename: Shalini
authors.initials: S
authors.lastname: Singh
authors.affiliation: e Department of Biochemistry , LHMC , New Delhi , India.
authors.forename: Ritu
authors.initials: R
authors.lastname: Singh
authors.affiliation: f Department of Obstetrics & Gynecology , LHMC , New Delhi , India.
authors.forename: Usha
authors.initials: U
authors.lastname: Gupta
authors.affiliation: g Department of Biochemistry , LHMC , New Delhi , India.
authors.forename: J
authors.initials: J
authors.lastname: Bhattacharjee
mesh_terms: D000328:Adult; D044466:Asian People; D001837:Body Weights and Measures / Q000379:methods* / Q000592:standards*; D003430:Cross-Sectional Studies; D018568:Crown-Rump Length; D005260:Female; D020567:Fetal Weight / Q000502:physiology; D005333:Fetus / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D005865:Gestational Age; D057238:Growth Charts; D006801:Humans; D007194:India; D016014:Linear Models; D048208:Nuchal Translucency Measurement / Q000592:standards; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012016:Reference Values; D016216:Ultrasonography, Prenatal / Q000592:standards
keywords: Ultrasound; biparietal diameter; first trimester; nuchal translucency