title: Effect of maternal anticonvulsant treatment on neonatal blood coagulation.
abstract: OBJECTIVE
  To investigate the impact of maternal anticonvulsant use on the ability of cord blood to coagulate.
  
  
  METHODS
  Cord blood prothrombin times were measured, over 15 years in a consecutive series of 137 term babies born to women taking phenobarbitone, phenytoin, and/or carbamazepine while pregnant. The response to parenteral vitamin K was measured in 83 neonates.
  
  
  RESULTS
  Only 14 of the 105 babies born to the mothers who had therapeutic anticonvulsant blood concentrations at birth had a prolonged prothrombin time (outside the 95% reference range). None had an overt bleeding tendency. The abnormality was corrected within 2 hours by 1 mg of parenteral vitamin K, but rapid intravenous prophylaxis produced complications in three infants.
  
  
  CONCLUSIONS
  A policy of giving vitamin K throughout the last third of pregnancy to all women being treated with anticonvulsants, as recently recommended, is not justified by the available evidence. The belief that there is a distinct, early form of neonatal vitamin K deficiency that is different from, and more dangerous than, the classic form of the disease, is not supported by a review of the published evidence.
authors.affiliation: Royal Victoria Infirmary, Newcastle upon Tyne NE1 4LP. shey@easynet.co.uk
authors.forename: E
authors.initials: E
authors.lastname: Hey
mesh_terms: D000927:Anticonvulsants / Q000009:adverse effects*; D001777:Blood Coagulation / Q000187:drug effects*; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007020:Hypoprothrombinemias / Q000209:etiology; D007231:Infant, Newborn; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000188:drug therapy; D011297:Prenatal Exposure Delayed Effects; D011517:Prothrombin Time; D014813:Vitamin K Deficiency / Q000097:blood*
chemical_list: D000927:Anticonvulsants