title: Biparietal diameter: a useful measure for determining gestational age of human abortuses.
abstract: BACKGROUND
  The crown-rump length is conventionally used to determine the age of human abortuses. However, it is not reliable as it is dependent on the positioning of the conceptus. We compared this with the biparietal diameter and foot length for determining the gestational age.
  
  
  METHODS
  Different measurements, commonly used to assess gestational age, were measured in 146 human abortuses for which an accurate obstetric history could not be elicited. Measurements taken were crown-rump length, biparietal diameter and foot length. These were correlated with the observations at antenatal examinations before finalizing the approximate age.
  
  
  RESULTS
  Multiple regression analysis of the data indicated that of the three measurements, the biparietal diameter was the most reliable for determining foetal gestational age between 8 and 26 weeks. The age determined with the biparietal diameter correlated well with that of abortuses with an accurate obstetric history.
  
  
  CONCLUSIONS
  The biparietal diameter of a human foetus may be used to determine its age if the obstetric history regarding the period of gestation is vague or not available.
authors.affiliation: Department of Anatomy, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
authors.forename: K
authors.initials: K
authors.lastname: Sailaja
authors.forename: R K
authors.initials: RK
authors.lastname: Ahuja
authors.forename: G
authors.initials: G
authors.lastname: Gopinath
mesh_terms: D000028:Abortion, Induced; D000886:Anthropometry; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005260:Female; D005333:Fetus / Q000033:anatomy & histology*; D005865:Gestational Age; D006801:Humans; D007194:India; D007231:Infant, Newborn; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D012016:Reference Values