title: Platelet count at term pregnancy: a reappraisal of the threshold.
abstract: OBJECTIVE
  To assess the safety of a new platelet count threshold for the definition of maternal thrombocytopenia late in pregnancy.
  
  
  METHODS
  A platelet count was performed in 6770 pregnant women late in pregnancy and in 6103 of their newborns as well as in a control group of 287 age-matched nonpregnant healthy women.
  
  
  RESULTS
  The prevalence of maternal thrombocytopenia (platelet count less than 150 x 10(9)/L) was 11.6%. The mean platelet counts (248 compared with 213 x 10(9)/L) and 2.5th percentile (164 compared with 116 x 10(9)/L) were significantly higher in healthy nonpregnant women than in pregnant women. Among thrombocytopenic pregnant women, 621 (79%) had platelet counts between 116 and 149 x 10(9)/L; none (0%; 95% confidence interval 0, 0.6) had complications related to thrombocytopenia, and none of their newborns had severe thrombocytopenia (platelet count less than 20 x 10(9)/L).
  
  
  CONCLUSIONS
  In healthy pregnant women, a platelet count over 115 x 10(9)/L late in pregnancy does not require further investigation during pregnancy and may be considered a safe threshold.
authors.affiliation: Department of Internal Medicine, University Hospital, Geneva, Switzerland.
authors.forename: F
authors.initials: F
authors.lastname: Boehlen
authors.forename: P
authors.initials: P
authors.lastname: Hohlfeld
authors.forename: P
authors.initials: P
authors.lastname: Extermann
authors.forename: T V
authors.initials: TV
authors.lastname: Perneger
authors.forename: P
authors.initials: P
authors.lastname: de Moerloose
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008875:Middle Aged; D010976:Platelet Count; D011247:Pregnancy / Q000502:physiology*; D011250:Pregnancy Complications, Hematologic / Q000175:diagnosis*; D012016:Reference Values; D013921:Thrombocytopenia / Q000175:diagnosis*